roverdose1 Posted May 18, 2009 Share Posted May 18, 2009 Hello every body,another new boy to the forum, can somebody please help me before my 1991 range rover 3.9 v8 (non cat) puts me in a padded room, the problem i have is this,it stops runing when ever it feels like it,it will run for weeks or it can be days,hours, the engine just cuts out and won't start again for at least 20 mins then it can run ok for the next 5 mins then cut out again or it can run for the next week/month before doing it again,it is very intermitent,it mostly does it when coming to a stop at traffic lights or juntions,the rangie is a mint low milage(67,000) automatic,non airspring model,when the engine does cut out i check for a spark right away and there is always a healthy one, (changed all ignition side (coil,plugs,dizzy,cap,rotor arm,leads,ect)so this leaves the fuel injection side,i have changed the ecu(twice)the main relay the fuel relay,the airflow meter,thepetrol temp sender,water temp sender,the fuel pump,(twice)disconected the speed transducer,changed the fuel filter,the thing is when the engine is running it runs like a dream,pulls like a train,it can do this for 200 miles or do it for 5 miles then it cuts out and wont start again unless left for a short period of time,also fitted new fuel pressure reg and checked all conecters,can some one please help me,i dont want to get rid of the range rover as i love it i also dont really want to convert it to a webber 500 carb but if needs must,any one got a cheep one for sale Ha! Quote Link to comment Share on other sites More sharing options...
FITZ Posted May 19, 2009 Share Posted May 19, 2009 Wow that's a lot of parts youve changed. How about the ignition amp,,, there's two types one on the dizzy and one under the coil. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted May 19, 2009 Share Posted May 19, 2009 Fer Christ's sake don't fit a Weber, you may as well point the fuel hose straight down the inlet manifold #1 suggestion would be ignition amp #2 would be the wire from the coil to the ECU (white/black) and the relay that is sometimes in its way, you can jump across the contacts (NOT the coil) of it to bypass it. #3 would be fuel pump relay (cheap) or fuel pump itself. Quote Link to comment Share on other sites More sharing options...
roverdose1 Posted May 19, 2009 Author Share Posted May 19, 2009 Wow that's a lot of parts youve changed. How about the ignition amp,,, there's two types one on the dizzy and one under the coil. thanks for the reply,i forgot to mention i had changed the ignition amp on the dizzy(yet another part ha!) but iam not sure about the one under the coil,i will investigate Quote Link to comment Share on other sites More sharing options...
roverdose1 Posted May 19, 2009 Author Share Posted May 19, 2009 Fer Christ's sake don't fit a Weber, you may as well point the fuel hose straight down the inlet manifold #1 suggestion would be ignition amp #2 would be the wire from the coil to the ECU (white/black) and the relay that is sometimes in its way, you can jump across the contacts (NOT the coil) of it to bypass it. #3 would be fuel pump relay (cheap) or fuel pump itself. thanks for the reply,are the webers really that bad on fuel ,i forgot to mention that i have change the ignition amp, will have a look at #2 surgestion,i have changed the fuel pump and relay all to no avail,will keep trying,thanks Quote Link to comment Share on other sites More sharing options...
SteveRK Posted May 19, 2009 Share Posted May 19, 2009 If its a case that the engine stops dead - without spluttering etc. suggest you concentrate on low tension related electrical stuff. Any of the wires connecting the ignition amp and coil and from coil to ecu can get brittle with age - try flexing them with the engine running and check the looms that emerge through the bulkhead on the driver's side near the brake servo. Does it have an alarm fitted? Ive had an instance where an aftermarket alarm cable was chaffing on a sharp edge and caused exaclty the problem you are experiencing. I only found it by accident when flexing any wiring i could get to under the bonnet with the engine running. Quote Link to comment Share on other sites More sharing options...
V8david Posted May 19, 2009 Share Posted May 19, 2009 Check earth straps as well. Mine was cutting out intermitently, cleaned/moved earth locations and all was fine. Worth a look and costs nowt for a change Quote Link to comment Share on other sites More sharing options...
roverdose1 Posted May 19, 2009 Author Share Posted May 19, 2009 If its a case that the engine stops dead - without spluttering etc. suggest you concentrate on low tension related electrical stuff.Any of the wires connecting the ignition amp and coil and from coil to ecu can get brittle with age - try flexing them with the engine running and check the looms that emerge through the bulkhead on the driver's side near the brake servo. Does it have an alarm fitted? Ive had an instance where an aftermarket alarm cable was chaffing on a sharp edge and caused exaclty the problem you are experiencing. I only found it by accident when flexing any wiring i could get to under the bonnet with the engine running. Hello,thanks for the advice,its one that i have not tried,i will give it a go asap,the range rover only has the standard anti theft device but i dont know anything about it,like how does it work,how does it stop the range rover from being stolen i was wondering if it was going faulty and causing the problem,but like i say i dont know anything about it.does anybody know what the standard settings are for the air flow mixture screw and the idle screw on the 3.9 hotwire fuel injection, somebody has messed about with them in the past and i would like to put them back to the standard setting,i cant find any information in the mannual,i would certanly appreciate it,thanks again for all the help Quote Link to comment Share on other sites More sharing options...
roverdose1 Posted May 19, 2009 Author Share Posted May 19, 2009 Check earth straps as well. Mine was cutting out intermitently, cleaned/moved earth locations and all was fine. Worth a look and costs nowt for a change Hi,thanks for the reply,i will give it ago asap and let you know,i was wondering if anybody knew the standard settings for the airflow mixture screw and idle screw i cant find any information on them anywhere,i know this is not causing my problem but i would like to put them back to where they should be,thanks a lot Quote Link to comment Share on other sites More sharing options...
SteveRK Posted May 20, 2009 Share Posted May 20, 2009 I wouldnt worry too much about air flow meter settings being the possible cuase - if it seems to run fine when its running then its likely to be about right Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted May 21, 2009 Share Posted May 21, 2009 I'd suggest, given the impressive list of bits you've changed, that you stop changing things and do some diagnostics - there is a full hotwire diagnostics manual in the tech archive. However, a dead cut-out could be some silly electrical fault like a dodgy ignition switch or as has been said a poor earth lead - do the simple & cheap/free stuff first before swapping any more parts! Quote Link to comment Share on other sites More sharing options...
roverdose1 Posted May 27, 2009 Author Share Posted May 27, 2009 I'd suggest, given the impressive list of bits you've changed, that you stop changing things and do some diagnostics - there is a full hotwire diagnostics manual in the tech archive.However, a dead cut-out could be some silly electrical fault like a dodgy ignition switch or as has been said a poor earth lead - do the simple & cheap/free stuff first before swapping any more parts! Hello again every body,i have managed to get around to checking the earths,a few were a bit rusty so i cleaned them up and made sure the others were alright.Tried wagling the wiring about(engine harness/low tension)while the engine was running and it just kept on purring away,not had a look at the ignition switch yet so thats next on the list,went out in it yesterday and did 35 miles it never missed a beat,iv had a look at the hotwire diagnostics in the archive and come to the conclusion that while the engine is running alright the diagnostics check would come out right, iam proberly wrong on this,i will have to wait untill it cuts out again and try.Thanks again for all the sugestions Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted May 28, 2009 Share Posted May 28, 2009 iv had a look at the hotwire diagnostics in the archive and come to the conclusion that while the engine is running alright the diagnostics check would come out right, iam proberly wrong on this,i will have to wait untill it cuts out again and try. Unfortunately you're probably right I had an intermittent problem on my old Range Rover (rough running rather than cutting out) which passed all the diagnostics and had me scratching my head - in the end I converted it to Megasquirt (an easy call for me, as I already had it fitted and running the ignition so it was just a case of wiring it up to run the fuelling too), and could then see on the laptop that I had an intermittent signal from both lambda sensors. Turned out both wires were broken internally. It's still worth going through the diagnostics, because it will eliminate a few things and if it doesn't throw up anything then it at least confirms we're looking at a genuinely intermittent fault. Plus, of course, it may conveniently play up while you're testing - you never know... My money's on dodgy wiring somewhere. Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted May 29, 2009 Share Posted May 29, 2009 My money's on dodgy wiring somewhere. Agree, or probably a dry joint on the ECU Quote Link to comment Share on other sites More sharing options...
SteveRK Posted May 30, 2009 Share Posted May 30, 2009 A simple check when it next happens is to listen for the fuel pump that runs for a couple of seconds when the ignition is switched on - if it does suspect electrical stuff first - if it doesn't look no further its fuel related. Theres plenty of relays and wiring under the driver's seat that includes the fuel pump and fuel injection system relays as well as the ECU Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.