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Ticking off my problems list


Shackleton
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Ok I've been whittling away at the teething problems after the initial success of my 3.5 to 3.9 transplant.

In a last ditch before I take the RR to the other end of the country for new years (and then dump a specialist with the problem in shame) I write to you guys to pick your brains.

The car is still misfiring - actually chugging would be more onomatopaeic.

Heres the low down:

I've fed it new; plugs, leads, rotor and dist. cap. That made it much smoother but didn't solve the prob.

It runs perfectly at idle, and all the way through the range when at standstill but it chugs like a learner driver in the mid range once under load. It barely happens when cold (but is still noticeable) and is much much worse after sitting in traffic.

Does it sound familiar to anyone. Could it be air getting into the induction where it shouldn't? Or could it be the coil?

Does anyone have any experience with a knackered coil or knackered ignition amplifier causing symptoms like this? (or a knackered anything causing this)

Sorry for posting about it again! :ph34r: Please help! I was proud that on the first startup there were no exhaust blows anywhere and all this jerking has created more then one :unsure:

George

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What colour are your plugs?

If they are black it could be running too rich when hot (given you say that it is almost OK when cold).

Check the cold start injector - is it stuck open? It would be a quick check to squeeze of fthe line going to it when hot to see if it makes any difference.(If the 3.9 has a cold start injector? - the 3.5 does anyway)

Failing that I'd consider possibly the coolant temp sensor.

Generally I would think if it was drawing air then it would tend to run a bit hotter (from running lean) and you would also get the odd backfire.

Ok I've been whittling away at the teething problems after the initial success of my 3.5 to 3.9 transplant.

In a last ditch before I take the RR to the other end of the country for new years (and then dump a specialist with the problem in shame) I write to you guys to pick your brains.

The car is still misfiring - actually chugging would be more onomatopaeic.

Heres the low down:

I've fed it new; plugs, leads, rotor and dist. cap. That made it much smoother but didn't solve the prob.

It runs perfectly at idle, and all the way through the range when at standstill but it chugs like a learner driver in the mid range once under load. It barely happens when cold (but is still noticeable) and is much much worse after sitting in traffic.

Does it sound familiar to anyone. Could it be air getting into the induction where it shouldn't? Or could it be the coil?

Does anyone have any experience with a knackered coil or knackered ignition amplifier causing symptoms like this? (or a knackered anything causing this)

Sorry for posting about it again! :ph34r: Please help! I was proud that on the first startup there were no exhaust blows anywhere and all this jerking has created more then one :unsure:

George

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You've no idea what a help that is!

(the 3.9 doesn't have a cold start inj. btw) Oh and there are no backfires, it actually runs really nice unitil it chugs.

I'm fairly sure the thermostat isn't opening so obviously thats gonna have an effect on the temp sensor right?

The old plugs were all black but had a little burst of white at the tip?

Am I right in assuming that if the thermostat isn't opening then the water isn't flowing past the temp sensor - instead its just basically slowly heating to a boil and that could cause a silly reading to go back to my ECU and that causes a miss??? Does that tally with a less pronounced miss when cold?

I'm replacing the thermostat either way this weekend... fingers crossed

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The temp sensor shouldn't really be effected by the thermostat IMHO. What can happen is it stops working correctly and thinks that the engine is cold all the time and thus causes to the ECU to overfuel the engine when it warms up causing the bad running.

this will IIRC be a seperate sensor to the one for the temp gauge (so the dash gauge will still read correctly.) I can't tell you where the sensor's will be as I have A diesel not a V8.

HTH

Pete.

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hmm I'm just realising the only temp sender talking to anything is the one that I have hooked up to the original wiring for the 3.5.

As in the ECU isn't connected to any temp sensor at all. Should I be scrambling to get that rectified?

As far as I know the only temp sensor talking to the ECU is the fuel temp and the only water temp on the lump is a single one on the manifold. There's another coolant sensor on the thermostat elbow but I belive thats for A/C and isn't important. (I don't have A/C)

EDIT: no wait maybe there is a water sensor just behind the disributor on the manifold - yeah I'm slowly remebering. And yeah it's connected... so I should change that for a known good unit. My specialist beter have on on the shelf.

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The 3.9 ECU does use 2 sensors, fuel rail temp and coolant temp.

There are in fact 3 on the engine, fuel rail temp, coolant temp to ECU and coolant temp to dash gauge.

Now if you're temp gauge is working, and there' sonly one of the coolant sensors connected, it has to be the guage sender that's connected.

The fuel rail one is obvious, theo coolant sensors are fairly close together, round about the thermostat housing somewhere. I'd go into the garage and look but it's blowing a hoolie out there just now.

Oh aye and the two coolant senders aren't the same either :blink:

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RE the hoolie - it passed over us yesterday... it's frickin freezin!

Don't wory about looking, I've remembered the sensor in question. I'll replace and fingers crossed!

Y'know it' amazing with injecton how the smallest thing will frick up everything. On my injected classic mini, the €3-fiddy coolant expansion tank cap gave up. The resulting excess heat knackered the coolant temp sensor, the H/G got toasted and I ended replacing everything including the boiled expansion tank. The cap was the last thing replaced...

I'm begining to think that in this case it was the thermostat that knackered the sensor, the cap got toasted as a result or any combination of the above. I don't think th H/G's have been effected yet cause the plugs weren't clean (I know it's not 100% proof).

Anyway send me good vibes thins weekend for a speedy solution. Winter is here and I don't have a garage to heat

Thanks fellas!

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Change the collant tempreture sensor first, thet are often subject to failure. They cost about £10 and take a few minutes to change. Once it''s changed youve eliminated that as a possible cause. See attached file and this may help......

The Coolant Temperature sensor

This sensor is located at the front of the inlet manifold in the coolant gallery.It can be mistaken for the Thermotime switch but this one is less bulkier. It gives a signal to the ECU for engine temperature so that the ECU can inject more or less fuel depending on engine temperature. It does not affect the cold start injector!

The Thermo-Time switch

The thermo time switch controls the operation of the cold start injector. It is basically a pair of contact points, one of which is mounted on a bi-metal strip. A heater coil is fitted around the strip. The system works when the ignition switch is in the "crank" position. Whenever the bi-metal is cold the points are closed and the injector is operated. During the time the contacts are closed the current is heating up the strip. After max.12 secs (depending on ambient temperature) the bi-metal opens the points and injection stops. When the engine is already hot the bi-metal strip prevents the injector to operate during cranking. Notice that the extra air valve uses the same basic principle of a heated bi-metal strip.

The cold start injector

This injector is located in the top of the plenum chamber. As its name indicates it injects additional fuel when the engine is cold and the engine is being cranked. The cold start injector injects continuously and not intermittently like the other injectors. The injector gets its signal directly from the Thermo Time Switch and is not switched or controlled by the ECU.

EFI_Info.pdf

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OK will do...

Thanks for the article - mines the though, with Lucas Hotwire system so no cold start injector etc. Y'don't happen to have the same doc for the Hotwire aye?

Get yourself a copy of the Range Rover workshop manual - it's nowhere near as nice and clear as that, but it should have all the info you need.

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Would it be wrong to suggest MegaSquirt at this point? :ph34r:

For the money you'll pay a specialist to sort it out you could bin the Lucas carp entirely and have something you can plug a laptop into to *see* what the sensors are doing, if one has gone permanently to 0% or 100% you know it's duff, likewise if it doesn't move with a known rise in engine temp for example.

For info, here is the MegaSquirt's temperature sensor lookup table for the Rover sensor, it will tell you what resistances you should be seeing at any given temp:

; Generated 24-04-2003 08:56:25 by MStoolsII 
; Rover SD1 V8-Range Rover 
; Rover SD1 V8 and Range Rover 3.5 with Lucas 4CU 
; Computed Steinhart-Hart coefficients: A=0.00127947  B=0.000259373  C=3.56954e-07
;	 2 Celcius =  4000 ohm
;	 74 Celcius =   362 ohm
;	 94 Celcius =   212 ohm
; For use with  2490 ohm bias resistor installed at R7.
THERMFACTOR:
;	          ADC 	 Fahrenheit - Celcius - resistance in ohms
DB	210T;	   0 - sensor failure, use limp home value.
DB	255T;	   1	  500 	 260 	     10 ohms
DB	255T;	   2	  413 	 212 	     20 ohms
DB	255T;	   3	  369 	 187 	     30 ohms
DB	255T;	   4	  340 	 171 	     40 ohms
DB	255T;	   5	  318 	 159 	     50 ohms
DB	255T;	   6	  301 	 150 	     60 ohms
DB	255T;	   7	  287 	 142 	     70 ohms
DB	255T;	   8	  276 	 135 	     81 ohms
DB	255T;	   9	  265 	 130 	     91 ohms
DB	255T;	  10	  257 	 125 	    102 ohms
DB	255T;	  11	  249 	 120 	    112 ohms
DB	255T;	  12	  241 	 116 	    123 ohms
DB	255T;	  13	  235 	 113 	    134 ohms
DB	255T;	  14	  229 	 109 	    145 ohms
DB	255T;	  15	  224 	 106 	    156 ohms
DB	255T;	  16	  218 	 104 	    167 ohms
DB	253T;	  17	  214 	 101 	    178 ohms
DB	249T;	  18	  209 	  99 	    189 ohms
DB	245T;	  19	  205 	  96 	    200 ohms
DB	241T;	  20	  201 	  94 	    212 ohms
DB	237T;	  21	  198 	  92 	    223 ohms
DB	233T;	  22	  194 	  90 	    235 ohms
DB	230T;	  23	  191 	  88 	    247 ohms
DB	227T;	  24	  187 	  86 	    259 ohms
DB	224T;	  25	  184 	  85 	    271 ohms
DB	221T;	  26	  181 	  83 	    283 ohms
DB	218T;	  27	  179 	  81 	    295 ohms
DB	215T;	  28	  176 	  80 	    307 ohms
DB	213T;	  29	  173 	  79 	    320 ohms
DB	210T;	  30	  171 	  77 	    332 ohms
DB	208T;	  31	  168 	  76 	    345 ohms
DB	206T;	  32	  166 	  74 	    357 ohms
DB	203T;	  33	  164 	  73 	    370 ohms
DB	201T;	  34	  162 	  72 	    383 ohms
DB	199T;	  35	  159 	  71 	    396 ohms
DB	197T;	  36	  157 	  70 	    409 ohms
DB	195T;	  37	  155 	  69 	    423 ohms
DB	193T;	  38	  153 	  67 	    436 ohms
DB	191T;	  39	  152 	  66 	    450 ohms
DB	189T;	  40	  150 	  65 	    463 ohms
DB	187T;	  41	  148 	  64 	    477 ohms
DB	186T;	  42	  146 	  63 	    491 ohms
DB	184T;	  43	  144 	  62 	    505 ohms
DB	182T;	  44	  143 	  61 	    519 ohms
DB	181T;	  45	  141 	  61 	    534 ohms
DB	179T;	  46	  139 	  60 	    548 ohms
DB	177T;	  47	  138 	  59 	    563 ohms
DB	176T;	  48	  136 	  58 	    577 ohms
DB	174T;	  49	  135 	  57 	    592 ohms
DB	173T;	  50	  133 	  56 	    607 ohms
DB	171T;	  51	  132 	  55 	    622 ohms
DB	170T;	  52	  130 	  55 	    638 ohms
DB	168T;	  53	  129 	  54 	    653 ohms
DB	167T;	  54	  128 	  53 	    669 ohms
DB	166T;	  55	  126 	  52 	    685 ohms
DB	164T;	  56	  125 	  52 	    701 ohms
DB	163T;	  57	  124 	  51 	    717 ohms
DB	162T;	  58	  122 	  50 	    733 ohms
DB	160T;	  59	  121 	  49 	    750 ohms
DB	159T;	  60	  120 	  49 	    766 ohms
DB	158T;	  61	  118 	  48 	    783 ohms
DB	157T;	  62	  117 	  47 	    800 ohms
DB	156T;	  63	  116 	  47 	    817 ohms
DB	154T;	  64	  115 	  46 	    834 ohms
DB	153T;	  65	  114 	  45 	    852 ohms
DB	152T;	  66	  113 	  45 	    870 ohms
DB	151T;	  67	  111 	  44 	    887 ohms
DB	150T;	  68	  110 	  44 	    905 ohms
DB	149T;	  69	  109 	  43 	    924 ohms
DB	148T;	  70	  108 	  42 	    942 ohms
DB	147T;	  71	  107 	  42 	    961 ohms
DB	145T;	  72	  106 	  41 	    980 ohms
DB	144T;	  73	  105 	  40 	    999 ohms
DB	143T;	  74	  104 	  40 	   1018 ohms
DB	142T;	  75	  103 	  39 	   1038 ohms
DB	141T;	  76	  102 	  39 	   1057 ohms
DB	140T;	  77	  101 	  38 	   1077 ohms
DB	139T;	  78	  100 	  38 	   1097 ohms
DB	138T;	  79	   99 	  37 	   1118 ohms
DB	137T;	  80	   98 	  37 	   1138 ohms
DB	136T;	  81	   97 	  36 	   1159 ohms
DB	135T;	  82	   96 	  35 	   1180 ohms
DB	134T;	  83	   95 	  35 	   1202 ohms
DB	133T;	  84	   94 	  34 	   1223 ohms
DB	132T;	  85	   93 	  34 	   1245 ohms
DB	132T;	  86	   92 	  33 	   1267 ohms
DB	131T;	  87	   91 	  33 	   1289 ohms
DB	130T;	  88	   90 	  32 	   1312 ohms
DB	129T;	  89	   89 	  32 	   1335 ohms
DB	128T;	  90	   88 	  31 	   1358 ohms
DB	127T;	  91	   87 	  31 	   1382 ohms
DB	126T;	  92	   87 	  30 	   1405 ohms
DB	125T;	  93	   86 	  30 	   1429 ohms
DB	124T;	  94	   85 	  29 	   1454 ohms
DB	123T;	  95	   84 	  29 	   1478 ohms
DB	123T;	  96	   83 	  28 	   1503 ohms
DB	122T;	  97	   82 	  28 	   1529 ohms
DB	121T;	  98	   81 	  27 	   1554 ohms
DB	120T;	  99	   80 	  27 	   1580 ohms
DB	119T;	 100	   80 	  26 	   1606 ohms
DB	118T;	 101	   79 	  26 	   1633 ohms
DB	117T;	 102	   78 	  26 	   1660 ohms
DB	117T;	 103	   77 	  25 	   1687 ohms
DB	116T;	 104	   76 	  25 	   1715 ohms
DB	115T;	 105	   75 	  24 	   1743 ohms
DB	114T;	 106	   75 	  24 	   1771 ohms
DB	113T;	 107	   74 	  23 	   1800 ohms
DB	113T;	 108	   73 	  23 	   1829 ohms
DB	112T;	 109	   72 	  22 	   1859 ohms
DB	111T;	 110	   71 	  22 	   1889 ohms
DB	110T;	 111	   71 	  21 	   1919 ohms
DB	109T;	 112	   70 	  21 	   1950 ohms
DB	109T;	 113	   69 	  21 	   1981 ohms
DB	108T;	 114	   68 	  20 	   2013 ohms
DB	107T;	 115	   67 	  20 	   2045 ohms
DB	106T;	 116	   67 	  19 	   2078 ohms
DB	105T;	 117	   66 	  19 	   2111 ohms
DB	105T;	 118	   65 	  18 	   2145 ohms
DB	104T;	 119	   64 	  18 	   2179 ohms
DB	103T;	 120	   64 	  18 	   2213 ohms
DB	102T;	 121	   63 	  17 	   2248 ohms
DB	101T;	 122	   62 	  17 	   2284 ohms
DB	101T;	 123	   61 	  16 	   2320 ohms
DB	100T;	 124	   60 	  16 	   2357 ohms
DB	 99T;	 125	   60 	  15 	   2394 ohms
DB	 98T;	 126	   59 	  15 	   2432 ohms
DB	 98T;	 127	   58 	  15 	   2471 ohms
DB	 97T;	 128	   57 	  14 	   2510 ohms
DB	 96T;	 129	   57 	  14 	   2549 ohms
DB	 95T;	 130	   56 	  13 	   2590 ohms
DB	 95T;	 131	   55 	  13 	   2631 ohms
DB	 94T;	 132	   54 	  12 	   2672 ohms
DB	 93T;	 133	   54 	  12 	   2715 ohms
DB	 92T;	 134	   53 	  12 	   2758 ohms
DB	 92T;	 135	   52 	  11 	   2801 ohms
DB	 91T;	 136	   51 	  11 	   2846 ohms
DB	 90T;	 137	   51 	  10 	   2891 ohms
DB	 89T;	 138	   50 	  10 	   2937 ohms
DB	 89T;	 139	   49 	  10 	   2984 ohms
DB	 88T;	 140	   48 	   9 	   3031 ohms
DB	 87T;	 141	   48 	   9 	   3080 ohms
DB	 86T;	 142	   47 	   8 	   3129 ohms
DB	 86T;	 143	   46 	   8 	   3179 ohms
DB	 85T;	 144	   45 	   7 	   3230 ohms
DB	 84T;	 145	   45 	   7 	   3282 ohms
DB	 83T;	 146	   44 	   7 	   3335 ohms
DB	 83T;	 147	   43 	   6 	   3389 ohms
DB	 82T;	 148	   42 	   6 	   3444 ohms
DB	 81T;	 149	   42 	   5 	   3500 ohms
DB	 80T;	 150	   41 	   5 	   3557 ohms
DB	 80T;	 151	   40 	   5 	   3615 ohms
DB	 79T;	 152	   39 	   4 	   3675 ohms
DB	 78T;	 153	   39 	   4 	   3735 ohms
DB	 77T;	 154	   38 	   3 	   3797 ohms
DB	 77T;	 155	   37 	   3 	   3860 ohms
DB	 76T;	 156	   36 	   2 	   3924 ohms
DB	 75T;	 157	   36 	   2 	   3989 ohms
DB	 74T;	 158	   35 	   2 	   4056 ohms
DB	 74T;	 159	   34 	   1 	   4124 ohms
DB	 73T;	 160	   33 	   1 	   4194 ohms
DB	 72T;	 161	   33 	   0 	   4265 ohms
DB	 71T;	 162	   32 	  -0 	   4337 ohms
DB	 71T;	 163	   31 	  -0 	   4412 ohms
DB	 70T;	 164	   30 	  -1 	   4487 ohms
DB	 69T;	 165	   30 	  -1 	   4565 ohms
DB	 68T;	 166	   29 	  -2 	   4644 ohms
DB	 68T;	 167	   28 	  -2 	   4725 ohms
DB	 67T;	 168	   27 	  -3 	   4808 ohms
DB	 66T;	 169	   27 	  -3 	   4893 ohms
DB	 65T;	 170	   26 	  -3 	   4980 ohms
DB	 65T;	 171	   25 	  -4 	   5069 ohms
DB	 64T;	 172	   24 	  -4 	   5160 ohms
DB	 63T;	 173	   23 	  -5 	   5253 ohms
DB	 62T;	 174	   23 	  -5 	   5349 ohms
DB	 61T;	 175	   22 	  -6 	   5447 ohms
DB	 61T;	 176	   21 	  -6 	   5547 ohms
DB	 60T;	 177	   20 	  -7 	   5650 ohms
DB	 59T;	 178	   19 	  -7 	   5756 ohms
DB	 58T;	 179	   19 	  -7 	   5865 ohms
DB	 57T;	 180	   18 	  -8 	   5976 ohms
DB	 57T;	 181	   17 	  -8 	   6090 ohms
DB	 56T;	 182	   16 	  -9 	   6208 ohms
DB	 55T;	 183	   15 	  -9 	   6329 ohms
DB	 54T;	 184	   15 	 -10 	   6453 ohms
DB	 53T;	 185	   14 	 -10 	   6581 ohms
DB	 52T;	 186	   13 	 -11 	   6712 ohms
DB	 52T;	 187	   12 	 -11 	   6848 ohms
DB	 51T;	 188	   11 	 -12 	   6987 ohms
DB	 50T;	 189	   10 	 -12 	   7130 ohms
DB	 49T;	 190	    9 	 -13 	   7278 ohms
DB	 48T;	 191	    9 	 -13 	   7431 ohms
DB	 47T;	 192	    8 	 -14 	   7589 ohms
DB	 46T;	 193	    7 	 -14 	   7751 ohms
DB	 45T;	 194	    6 	 -14 	   7919 ohms
DB	 45T;	 195	    5 	 -15 	   8092 ohms
DB	 44T;	 196	    4 	 -15 	   8272 ohms
DB	 43T;	 197	    3 	 -16 	   8457 ohms
DB	 42T;	 198	    2 	 -17 	   8649 ohms
DB	 41T;	 199	    1 	 -17 	   8848 ohms
DB	 40T;	 200	    0 	 -18 	   9055 ohms
DB	 39T;	 201	   -1 	 -18 	   9268 ohms
DB	 38T;	 202	   -2 	 -19 	   9490 ohms
DB	 37T;	 203	   -3 	 -19 	   9721 ohms
DB	 36T;	 204	   -3 	 -20 	   9960 ohms
DB	 35T;	 205	   -4 	 -20 	  10209 ohms
DB	 34T;	 206	   -6 	 -21 	  10468 ohms
DB	 33T;	 207	   -7 	 -21 	  10738 ohms
DB	 32T;	 208	   -8 	 -22 	  11020 ohms
DB	 31T;	 209	   -9 	 -23 	  11313 ohms
DB	 30T;	 210	  -10 	 -23 	  11620 ohms
DB	 29T;	 211	  -11 	 -24 	  11941 ohms
DB	 28T;	 212	  -12 	 -24 	  12276 ohms
DB	 27T;	 213	  -13 	 -25 	  12628 ohms
DB	 25T;	 214	  -14 	 -26 	  12997 ohms
DB	 24T;	 215	  -15 	 -26 	  13384 ohms
DB	 23T;	 216	  -16 	 -27 	  13791 ohms
DB	 22T;	 217	  -18 	 -28 	  14219 ohms
DB	 21T;	 218	  -19 	 -28 	  14671 ohms
DB	 19T;	 219	  -20 	 -29 	  15148 ohms
DB	 18T;	 220	  -21 	 -30 	  15651 ohms
DB	 17T;	 221	  -23 	 -30 	  16185 ohms
DB	 16T;	 222	  -24 	 -31 	  16751 ohms
DB	 14T;	 223	  -25 	 -32 	  17352 ohms
DB	 13T;	 224	  -27 	 -33 	  17992 ohms
DB	 11T;	 225	  -28 	 -33 	  18675 ohms
DB	 10T;	 226	  -29 	 -34 	  19405 ohms
DB	  9T;	 227	  -31 	 -35 	  20187 ohms
DB	  7T;	 228	  -32 	 -36 	  21027 ohms
DB	  6T;	 229	  -34 	 -37 	  21931 ohms
DB	  4T;	 230	  -36 	 -38 	  22908 ohms
DB	  2T;	 231	  -37 	 -38 	  23966 ohms
DB	  1T;	 232	  -39 	 -39 	  25117 ohms
DB	  0T;	 233	  -41 	 -40 	  26371 ohms
DB	  0T;	 234	  -43 	 -41 	  27746 ohms
DB	  0T;	 235	  -44 	 -42 	  29258 ohms
DB	  0T;	 236	  -46 	 -44 	  30928 ohms
DB	  0T;	 237	  -48 	 -45 	  32785 ohms
DB	  0T;	 238	  -51 	 -46 	  34860 ohms
DB	  0T;	 239	  -53 	 -47 	  37194 ohms
DB	  0T;	 240	  -55 	 -48 	  39840 ohms
DB	  0T;	 241	  -58 	 -50 	  42864 ohms
DB	  0T;	 242	  -60 	 -51 	  46352 ohms
DB	  0T;	 243	  -63 	 -53 	  50422 ohms
DB	  0T;	 244	  -66 	 -55 	  55233 ohms
DB	  0T;	 245	  -70 	 -56 	  61005 ohms
DB	  0T;	 246	  -73 	 -58 	  68060 ohms
DB	  0T;	 247	  -77 	 -61 	  76879 ohms
DB	  0T;	 248	  -82 	 -63 	  88217 ohms
DB	  0T;	 249	  -86 	 -66 	 103335 ohms
DB	  0T;	 250	  -92 	 -69 	 124500 ohms
DB	  0T;	 251	  -99 	 -73 	 156248 ohms
DB	  0T;	 252	 -108 	 -78 	 209160 ohms
DB	  0T;	 253	 -119 	 -84 	 314985 ohms
DB	  0T;	 254	 -138 	 -94 	 632460 ohms
DB	210T;	 255 - sensor failure, use limp home value.

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Not wrong at all mate, it's just that this build was a first for me and even though the mech's and specialists that have seen what I've done have been impressed and said it's a lovely clean job the reality is it took a lot out of me.

I started in late August and only got it going about 3 weeks ago. In the mean time I had to do things to my very original car that I really didn't want to but the time pressure had me thinking all wrong and just wanting to get it done. So basically my enthusiasm is dwindling big time (and I have a **** lot of it - you know how it works) so I just need to get through the winter and to some decent weather, get the chance to rebuild the enthusiasm and my wallet and then I'll be pestering your ass about MS :D

MS is almost a must for me as I'll feel much better knowing that I have a brand new, 100% diagnosable management system instead of a largely unknown 17 year old, specialist diagnostics equipment needing one.

- thats all assuming the MS isn't doable from what you get told in an email and for about 3p?

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Or maybe I'll go delete your account you blasphemer! B)

:lol: didn't realise that TD5 was a punishable sin!

Ok I continue F'ing the atmos in the A with the beautiful but carbon happy V8. - Thats the real reason I'd love to go diesel, that and getting down the local chippy for some free go go juice...

*hippy mode off* :ph34r:

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It won't plug in - you need to cut the Lucas ECU connector off (or for a bit extra if you can find a dead Lucas ECU I can make an adapter cable) but it's only joining wires together, here's Dan's halfway through:

newplug.jpg

We took the approach of crimping a spade connector on to each wire to join it, you could do it by soldering together or even soldering the wires straight to the ECU connector, however that's not massive fun trying to solder in a vehicle and if the loom is old it can give variable results.

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Have you checked that you have the correct plug onto each sensor ? It is possible to swop the fuel rail temp sensor plug for the coolant temp sensor.This confuses the engine ecu as from cold both will read the same,but soon the coolant temp will be up to 90 odd degrees but the rail temp is usually in the 30's.Swopped around plugs just make the ecu think the engine is still cold, run wide pulse widths for the injectors hence your rich mixture and chugging.

Dont give up on the 14cux system it is a very good reliable system,capable of closed or open loop control with proper control of idle speed as well.For the first time ever a Rover V8 ran properly,giving good power and emissions for long periods - something never achieved with previous systems,either efi or carbs.

It is also very cheap to repair,and with the correct info easy to faultfind.Megasquirt is an interesting project to play with,but using s/h bits from breakers can be just as fullfilling.Lastly,even tho you can use Testbook to read codes from it and do live data readings,I rarely bother with it as the trusty Fluke meter is just as quick.(Not that they give many problems,excepting AFM's blown up by LPG backfires)

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I'll double check Ally but I used masking tape and biro to mark every connection as I removed the loom to make sure I didn't mistake anything... still my brain, masking tape and biro are not infallable ;)

Fridge - I'm glad you said they're spade connections, at first glance I saw scotch blocks and was cowering! Thats some work right there, you're some man for one man.

So a knackered temp sensor / rich mixture can really cause a motor to chug? I'd started to convince myself that it couldn't! Here's hoping. We'll all find out tomorrow...

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Yes,in UK market RR's from about 89-92 and in some Discovery 3.5 v8's from similar years too.Not sure about other world markets,I expect Saudi and middle East market ones were open loop.It is simple to change from closed to open loop,just swap the tune resistor situated in the main engine ecu loom about a foot from the ecu plug,for a market territory that does not use cats/oxygen sensors.

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Yes,in UK market RR's from about 89-92 and in some Discovery 3.5 v8's from similar years too.Not sure about other world markets,I expect Saudi and middle East market ones were open loop.It is simple to change from closed to open loop,just swap the tune resistor situated in the main engine ecu loom about a foot from the ecu plug,for a market territory that does not use cats/oxygen sensors.

Ah! That explains why there were no Lambda sensors on the one I took the exhaust off this week :)

I'm selling it to Rogue Trooper so I was a bit concerned someone had been up to some bodgery, but it's an '89, so that would be right.

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Yes,in UK market RR's from about 89-92 and in some Discovery 3.5 v8's from similar years too.Not sure about other world markets,I expect Saudi and middle East market ones were open loop.It is simple to change from closed to open loop,just swap the tune resistor situated in the main engine ecu loom about a foot from the ecu plug,for a market territory that does not use cats/oxygen sensors.

Ahh! (light goes on) for years I have been wondering what that tune selection resistor does... So is this another point that would need checking in case of troublesome running symptoms - that the tune resistor is ok?

Rog

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:lol: *makes buble buble noise with finger between lips*

Fellas I have no clue what your talking about but I'm getting a serious sinking feeling.

My 3.9 has no lambdas/cats and a tune resistor thingy under the seat - what does that mean?

Oh let me guess, it means theres another varible in my quest for a sweet running engine :unsure:

EDIT: and it's certainly a UK car as the front of the original rad was salt mangled - we don't salt our roads.

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