ramon alban

Comprehensive RV8 Electronic Ignition PDF's available from these links Here for Rover SD1 V8 Electronic Ignition - Description and Analysis Here for Rover SD1 V8 Electronic Ignition - Components and Testing owners moggydawed by Electronic Ignition can redress the balance and, hopefully, report back any O's & E's. Ramon www.vintagemodelairplane.com

Helo Onne, Only have experience with earlier SD1 system, but two possibilities come to mind: # The ignition amplifier is dying, when hot and killing the ignition, only to recover its vitality when cold and temporarily give you back the missing sparks. # Ignition amplifiers have a finite lifetime typically in the range 60,000 - 100,000 miles Alternatively # Your tacho dying as engine stalls suggests an intermittent connection from Coil Negative directly to the Tacho and via a Trigger Resistor to (normally) pin 1 of the ECU. # Check all the White/Black wiring connections there-abouts for integrity, corrosion, breaks. # Hopefully this circuit should be similar to yours. Forgive me if these are false trails. Ramon www.vintagemodelairplane.com

What the heck happened after this? Repeat, well at least it stays running at a reasonable rpm now, If by fiddling with the ECU multiplug the problem virtually disappeared and it has since returned, my conclusion would be to revisit the same place again. Are you able to see any damaged contacts on the multiplug. Also they lose their springynees and can be tweaked/adjusted with a wooden kebab stick. If I misunderstood the above quote, I apologise, but I cant see where it says the variable rpm was still a problem, then? So it must have returned - worth looking at that solution again, methinks.

Niki, You need to check the plug condition and report back, to assess how bad the mixture problem is? Your trigger signal is working OK otherwise the engine would not run at all. The ECU fires the injectors each bank of four alternately. Read the articles on my website to understand everything. The reason your tps is not getting to 4.3 volts is EITHER 1 the wrong TPS with 105 degrees of rotation (not a serious problem) OR 2 there is a mechanical restriction not allowing throttle to open fully. To "think" the FPR is not working is an important observation and could be your problem, but you must measure the fuel pressure as specified in the FPR article on my website. The fuel pressure should vary from 26 - 36 psi depending upon throttle activity and engine load. The article explains how/why. Is the FPR vacuum tube OK? Did you actually measure the temp sensor reading at the ECU multiplug? If not, your ECU may not be seeing the sensor correctly. Regarding broken ignition - ignore for the time being, your engien runs, but with a mixture problem not an ignition problem.

OK! At the getgo of these systems, Bosch/Lucas had to devise a way of making a combustible mixture available when the engine was on Overrun (typically, fast downhill with throttle shut) and by using the very high vacuum generated on overrun, open a valve to allow in more metered air and thereby correct the mixture, thus averting unburned fuel popping and banging in the v. hot exhaust system. Time moved on and Rover decided to eliminate the problem in later systems, like yours, by having the vacuum operate a vacuum controlled relay to cut the engine running signal from coil neg to pin 1 of the ECU. Now with therunning signal absent, the injectors never opened on overrunn so no uncombusted fuel passed thro' into the exhaust. Same result, no popping and banging and a bonus of slight improvement in emissions and economy. Its not quite as simple as it sounds, indeed the science behind it is quite deep, but I have made a decent stab at a full explanation. Most owners dont give a damn about this but when things go wrong, as they did with you, an understanding of whats happening brings clarity to the issue - so read this study at your peril: http://www.vintagemodelairplane.com/pages/Rover_Technical/Overrun02.html Oops! Your mud covered relay had good reason to croak irrespective of its lightly loaded function. Tee hee!

Hello Niki, # That black smoke without the smell of burning oil is due to rich mixture, I reckon you will find your spark plugs black/sooty too. # The likely cause is the temp sensor or even your replacement resistor is not being seen by the ECU due to a faulty connection from sensor to ECU or a faulty earth connection from the Efi loom to the engine block. # Check you measurements at the ECU multiplug, or simply inspect, clean and carefully fettle the contacts there-in. # All the above is usual suspect number 1. # This essay explains how to perform the tests, but your ECU may be different to the one described: http://www.vintagemodelairplane.com/pages/Rover_Technical/TempSensor01.html Other suspects are: # Faulty FPR causing fuel pressure to remain constantly high. # Vacuum tube not connected to FPR - with likewise effect. # Noisy/damaged throttle pot. # Blocked air filter You might wish to read my essay about diagnosing the colour of exhaust smoke: http://www.vintagemodelairplane.com/pages/Snippets/Smoke01.html Check it out!

Your problem was sequential. Your croaking battery was not well enough to fire the mixture on the first couple of starts, by which time the engine had flooded. Your weak battery now stands no chance but the flooding continues with each attempt to start, Fitting a new battery was never going to work without first unflooding the engine by either cranking with pump disconnected and throttle wide open, OR, cleaning all the plugs before the retry.

Which I guess is pretty much the same as this suggestion: Also, How was it faulty? Not responding to vacuum? Vacuum not connected? Relay contacts permanantly open? Did you destroy a good relay, one wonders? Did you replace the faulty relay or simply join the wires to bypass it? Reason I ask, is, those relays with little or no load, dont usually croak!

Your wet plugs may have been caused by continually trying to start the engine so the cold start injector has been pumping fuel every time the engine cranks. As 'Ally V8' mentioned, a flooded engine is a pig to fire up. If so (and perchance) there may be no evidence that the fuel is coming from the normal injectors. If they are not firing, then there are three possible reason 1 the trigger signal from coil negative to the ECU has not been reconnected 2 the ECU is broken 3 the wiring loom/ECU multiplug connector is not seated or some earth connection is missing, or some other wiring loom issue. For a unique and comprehensive analysis of all the EFI components have a browse thro this archive. http://www.vintagemodelairplane.com/pages/Rover_Technical/EfiComponents01.html

Why? You have almost certainly found the fault, by following the highlighted advice in my first post, #9: If its running at 98% the remaining 2% won't be found inside a fresh ECU. Finish the ECU multiplug cleanup as suggested and move on to an overall health check for your Efi system (used to be known as a tune-up). I have documented fifteen things a boy can do under the psuedonym of eliminating power losses (but, whats in a name?). http://www.vintagemodelairplane.com/pages/Snippets/MorePower01.html Being keen on finding the lost percentage will mean extreme diligence addressing those 15 items. Indeed, with a bit of luck, you'll probably find more than the missing 2%. By its nature, when faced with methodical advice, one is tempted to miss out some steps! If so, think about the young bull who said to the old bull, "Look! There are some cows in the meadow! Let's run down do a couple". The old bull replied, "Nah! Let's walk down and do the lot! Otherwise, you'll never know how much fun you coulda had!"

Any idea what the condition of the spark plugs is like after the engine has stalled?. Check at least one plug from each bank. preferably a couple. Looking for black/wet condition indicating overfuelling. If one side is ok and the other is black/wet then its a cinch for ECU problem. If both sides wet/black, we are still looking for ECU or temp sensor connector probs. Also possible fuel pressure regulator failure, or a really BAD throttle pot. If there is no evidence of black/wet then fuel starvation as mentioned in new posts is a distinct possibility.

Hello Nige, All the above is so very true and even as most of the components themselves were pretty much bulletproof (with a couple of exceptions), the worst enemy of our Flapper systems today is dirt and neglect. As purchased and for several years thereafter original sharp suited owners had their Full Service History, and dependent wholly upon their franchised service agent, the flapper systems held up pretty well, despite the original cost vs quality issues you mentioned. Then the 2nd, 3rd and 4th generation of owners took over, dropped their routine servicing down to brake pads, oil and filters and completely overlooked cleanliness and wiring connector/air pipe security. Thus it came to pass, crudded up throttle and plenum chamber, blocked breather, corroded connectors, split rubber tubes, emerged tenfold, thus our sad/old flapper systems got themselves into a terrible state and started to give up the ghost, ad nausium. Now, all new owners came to believe some sort of black art was required to diagnose fault conditions and all this time fewer and fewer flapper-wise technicians populated the planet. Woe, Woe and Thrice Woe! Now the hobbyists come onto the scene - from 1993, I'm one - and bemoaned a lack of expert help, even then. So for them there was/is really only one solution - DIY and internet forums. To that end, I had to overcome and combine my complete ignorance of motor cars and fuel injection systems with my diagnostic career in hi tech, persuading myself that this could not be rocket science. I just needed an edge. And so it came to pass, I acquired a copy of the LR Technician Training Manual and Video for the Flapper Efi and set my sights of becoming self-sufficient. Without that training manual nothing made sense. It was the key to the door and the bible from which everything else flowed. After the first few years with my car I knew enough to be confident to write it all down again, not in tech training terms, but a changed lingo that the DIY home mechanic could assimilate in Club magazines, journals, etc, all too early for the internet, then, of course. Now, with more knowledge and refinement plus the power of my own website, the end result is what appears on my web pages and, I agree 100% with you - patience, and a structured methodical approach is the key to success for the enthusiastic hobbyist. For those who cant do this thing, it leaves only the expensive scattergun approach to component replacement whilst sadly overlooking 80% of the likely causes, air leaks and connection problems, undiagnosed and still part of the perceived black art. A better alternative to scatterguns is to clearly gather up all the signs and symptoms, state the car and the system, post it all on one of the various available forums (forii?) and let the dogs loose. Trouble is, even when answers seem to be logically analysed and proposed, sometimes an originator reverts to the scattergun, and like an oil tanker on collision course, no amount of pleading can change the turn of events. Its a shame but thats the truth of it.

If, after you have tried a known good working ECU, the fault persists, you may choose to look again at the temperature sensor that has a 80 to 100 degree C resistance of 300 to 150 ohms, and yes, the early flapper engine will fire and run from cold with an open circuit sensor, running progressively more rich up to the point where it croaks, somewhat as you describe in your first post. Surging or hunting is a possible symptom of a fault condition usually induced by a rich mixture occuring somewhere in the warm-up cycle. Mostly at idle, but capable of occuring at higher rpm. It is usually transitory, but when severe, eventually manifests itself in a "surge too deep" where-upon the engine dies. Read about Flapper system Hunting here: http://www.vintagemodelairplane.com/pages/Snippets/EfiHuntingSolutions01.html The ECU can and does play up but it has multiple fail modes so none are particularly "classic" except perhaps gross overfuelling on one bank of four cylinders in which case the engine floods from the getgo. Lets hope it is the ECU, for an easier fix.

George, I am completely mystified by your comment when its been explained with several replies that we are primarily dealing with a temperature related, and possibly intermittant, fault due to dodgy coolant temperature sensor and/or its associated connector and wiring and only as a secondary suggestion, perhaps air leaks might come into play. Yet you have rechecked air leaks and the distributor when there is very low possibility of an ignition fault and totally ignored the prime suspect - Temp sensor and its wiring. Also no feedback from you what is the condition of the spark plugs, a key indicator for mixture problems. Its just occurred to me that you dont have a multimeter or the skills to use one and if that is the case, please either read about using a multimeter here: http://www.vintagemodelairplane.com/pages/Snippets/Multimeter01.html or get some help from someone who can use one.

Hello George, your scattergun approach, replacing all those very robust and expensive components does not generally work. First, I'm guessing its a Flapper AFM System, running on petrol and/or lpg? As you have replaced so many components without success one needs to turn to analysing the symptoms. I'm also pretty sure that upon inspection you'll find the Spark Plugs will be black or wet. Thus, it's clearly a temperature related fault with (assuming) wet/black spark plugs as I describe, so I'll wager its starting to run too rich During and After the warm up process resulting in your reported Hunting, Stalling and Lumpy Combustion process. The problem, therefore, must be the Coolant Temp Sensor or its connections are open circuit causing overfuelling when warm/hot. Just changing a component will not expose dodgy connection problems, so test all the aspects of the CTS and its wiring as per the following link: http://www.vintagemodelairplane.com/pages/Rover_Technical/TempSensor01.html You should be looking for broken CTS connector contacts, broken wire in the Efi loom, dodgy/corroded earth connection on the engine block studs behind and below the L/H rocker cover, faulty connection in the contacts of the ECU multiplug. Fix the latter carefully with a wooden kebab stick. For good measure, and to last a lifetime, clean and spray WD40/Switch cleaner into all Efi wiring loom connectors and fill with vaseline before reconnecting. Regarding air leaks, although unlikely to be the primary cause, they are also a contributing possibility. To run a full set of tests, see here: http://www.vintagemodelairplane.com/pages/Rover_Technical/Plenum01.html Its a sad statistic, approx 80% of all Flapper System faults are due to air leaks and/or electrical connection issues. For more info on the flapper system similar to yours, check out all the Efi system component essays in the Efi archive on my website. In addition you may wish to study an Efi Operations Manual, where the whole kit'n'kaboodle is fully explained. You'll be amazed! If you car is not a 3.5 flapper, None of the above applies. For anyone curious about the common cause of Efi Hunting - look here: http://www.vintagemodelairplane.com/pages/Snippets/EfiHuntingSolutions01.html