Car won't idle

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JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Hi mate....

I tried loading up the avi last night.. all I got was a sound file.... tried it at work too.. still a sound file ??! Must be doing something wrong.

The tapping / smoking I'm guess can be a exhaust track thats cracked .. usually audiable when cold... like a high pitched tapping... Smoke probably the enrichment coming out of it... unless it smells like oil....

I'm at a bit of a stumbling block with yours...

A suggestion... the fuel pump works at two speeds... the relay drives a 9 volt circuit and a 12 volt circuit.. One for idling and one for driving... see where I'm going here ??!!

I have read of people losing the 9 volt ( resistance ) circuit.. which evidently causes the thing to cut out. The trick around it is to go into the fuse box and pull the fuel pump relay and get 2 spades and a piece of wire and wire it up so it runs the 12v circuit... you'll have to do a search on here... "fuel pump mod" - I did this years ago but can't remember which way round it is !

On this subject... could be worth checking the fuel pump relay is switching correctly !! :-k

:-k what havent we covered in getting the thing to idle.... ??!! have you wire up the idle control valve circuit correctly, to allow the ecu to control its idle ??!! Check continuity ?!!

:D
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Sorry, the avi is encoded with DIVX (so without the DIVX codec it will only play as an audio stream).

Sorry for the retention of knowledge, but I forgot to mention the guy who had it before me has fitted an in-tank walbro. Don't know if that makes a difference.

I think I've seen something on testing the fuel pump relay so will have a look at that, I also read something on here about just attaching a permanent live to the necessary terminals on the ICV to make sure it is receiving the open signal, I might try that too.

Is a cracked exhaust track bad?
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Is a cracked exhaust track bad?


Let me elaborate... if it is.. its a crack in the exhaust manifold or perhaps the manifold gasket ... the noise it reproduce by the track / the channel of air coming from the cylinder thats just undergone combustion....

Least of your worries at the moment....

I'll try and down load it again later, I'm an engineer not a IT boffin !! :mrgreen:

Walbro will still need to take the same feed.. I'm not sure if it'll work with a 9V feed ?? could be the key .. some pump / motors wont operate uner 10V's !!

Still say you'r enot a million miles away buddy... so keep your chin up !! :thumleft:
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Maybe we could trade brains for a day :lol:

I could sure do with your knowledge for a day. To help you out with viewing the video, if you go to the link below it will download the codec needed to view the video. If you'd prefer not to download and install it, I can always post it again in a more universal format once I get home.

http://download.divx.com/divx/DivXInstaller.exe
Last edited by Shmed on Fri May 08, 2009 2:56 pm, edited 1 time in total.
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Just from the sound of the engine on the video, would you say the internals of the engine sound ok (I know that is a bold statement to make from just a bit of audio)?
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Should the turbo carry on smoking after the engine is switched off? If there was an air lock in the coolant, would the turbo get hotter quicker? I only ask because when I took the TB off last time, I didn't get any coolant come out of the pipes when I removed them, and I don't think I properly drained the system.
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Ok, I have just wired the ICV directly to the battery and the car still doesn't idle. If I wire the ICV closed then it runs badly all the time though. I did notice that there doesn't seem to be a wire coming from the ECU where the RSO should be. I'll get a photo.

I noticed that when starting the car the boost gauge goes about half way up the scale, but once the engine is running, it just goes down to the bottom of the gauge and doesn't move again.

I'm off out to check the fuel relay thing now.
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

I know it seems that I'm talking to myself.......

Here are the pics of my spark plug (all four of them look like this (I have gone back to basics and am just checking everything)

Image

And here are some pictures of the wires coming out of the ECU - some cables have been spliced, but they still seem to connect to the right colour.

Image
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Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

And here are the pictures marked up with ECU connector info from the BGB:


The most notable problem I can see is that there seems to be no connection to the RSO pin on the ECU which I guess means the ECU has no control over the opening of the Idle Control Valve :shock:

I guess a lot of the connectors that are populated on mine and not on the BGB pin guide are because my guide is for a 91 :oops:
Last edited by Shmed on Mon May 11, 2009 3:05 pm, edited 1 time in total.
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Ok, ignore the comment about the RSO pin, and the photos of the ecu being m,arked, as those markings are for a Rev1. I now have the rev2 wiring diagram, and the RSO is connected fine.

Tried a few things today, ran new wires to the ICV as I didn't have continuity (or so I thought). The car works with my new cable, but it is no better than it was on the standard cables, so I don't think it is that.

I have now drained and refilled the coolant properly as I thought that might have something to do with the turbo getting hot.

Cut a long story short, the car still doesn't idle, is very hard to keep at steady revs and I noticed that the exhaust gases coming from the tailpipe are VERY hot (as in I can't put my hand in front of the exhaust it's that hot, hot). Anyone got any ideas?

Compression test is next 8-[
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

So, I've bought my compression tester and will be doing that tonight.

Would I be right in sasying the plugs are black because my mixture is too rich? Would it be fair to say that the mixture being too rich might cause my not idling issue?

I am going to check the MAP sensor is working right later, and that the ECU is seeing all the right voltages at the next opportunity. God it will be satisfying to get this xxxxx running. JJ, I have looked up the fuel pump mod, but haven't done it yet. Will let you know the results when I get round to it.

Not sure if I have made it clear, but the car doesn't just stall when I take my foot off the pedal, it is very hard to keep it running iof the revs drop below 2000. The turbo housing also starts to smoke (as if it is burning oil off the outer housing) within 2 minutes of the engine being turned on, can anyone verify if that is normal?
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Would I be right in sasying the plugs are black because my mixture is too rich? Would it be fair to say that the mixture being too rich might cause my not idling issue?


Schmed - Your engine is cutting out because of overfuelling I believe or ogt a vac leak somewhere..... I've always thought that... I'd try to create more air going into the manifold. You can probably try pulling one of the vac lines off to see if it'll run... ( this could point at the afm being faulty )

Dont waste your time on the map sensor... I starting to think its the AFM.... is that wired up correctly ??!!

It does sound like its just flooding the bores with fuel.. and no real control of fuelling !??! Is there a fuel pressure regulator on it ??!!

Wonder if you can check to see if the rail is under constant pressure.. its possible that intial start is allowing petrol to go it, if the rail pressure isn't right ( ie. FPR failure ) ... it'll spray to fire it up, but wont allow it to run smoothly.. ??!! :-k

I'd look at :

Fuel pressure regulator - Bridge FP and B+ in the diagnostic port.. this will make the fuel pump run continuously without the engine running... Out fo curiosity.. try firing it up and see if it'll run ?!?!

Air Flow meter - its possible the things been apart and refitted incorrectly.. the brush contacts maybe in the wrong position and thus overfuelling the engine through mal adjustment or simply a short...

Getting there... process of elimination.... better not be somethings stupid, you'll be kicking yourself for weeks !! :mrgreen:

Got petrol ??!! :-$
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Got petrol, yes :clown: , it is only crappy Morrisons stuff though. If I pull one of the vacuum lines off and he engine runs as it is now, what does that mean?

Would the overfuelling cause high exhaust temps?

I have got the FPR fitted, but can't guarantee it is working. I'll try the diagnostic later.

Cheers (hopefully be sorted soon)
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Would the overfuelling cause high exhaust temps?


How do you know you're getting high EGTs ???

At the end of the day, combustion is taking place, so you'd expect it to get hot... even if the car only starts to fire and not run.. it'll soon warm up the manifold / turbo assembly.

I can't see any dangerous EGT's on initial start up, the cars not been running longer than 5 mins.. and its not under load to cause problems .. lack of fuel will just make it cut out or unable to rev up correctly....

Cheers
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

It's just the speed at which the turbo housing starts to smoke. I'd expect it to get hot, maybe I'm just a bit paranoid having put it back together myself :neutral:

I have checked the AFM this morning and it checks out fine, all continuity checked, the resistances are within tolerances at rest, and when I move the flap the resistance is within range - does that rule the AFM out?

I also did the fuel relay thing and I can hear the pump come on - still doesn't stay running though.

I reckon I must've missed something obvious - probably with the vac lines like you first suspected. I'm gonna go and do another quick visual check to make sure all the hoses are on and not split :scratch:
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

The one that usually splits is the afm to turbo hose... usually splits out of sight... check it thoroughly... bend it, twist it !! :D

It is frustrating even from this end to see it still not work even though you've practically saturated everything !

Rule AFM out if you're getting all the correct values ! :thumleft:
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

Can't wait for all this trouble to be a distant memory when I'm racing round a track.... Know it'll be worth it.

I haven't found anyhting obvious on any of the pipes, but will start taking them off later to give them a thorough once over. I did a compression check (170 pretty much across the board) so that's reassuring. The wisps of smoke I was getting from around the inlet manifold (as the car died) appear to be coming from the backbox - midpipe join, so a bit of Gun Gum probably required there.

Will the 'Test' mode tell me more do you think? I never noticed it in my 91 BGB, but now I have t he 93 one, it seems to provide more detail.

Do you know of a 'trial & error' approach I can take with the vac lines? Like, pull one off and see if it makes it worse/better, then block it off or something?
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Just out of curiosity, have you had the whole intake manifold off ??!! Theres a butterfly mechanism which is the T-VIS .... its an actuated plate between the manifold and the head... it has a gasket on both sides....

Often people do gut them.. if not dont correctly, can be drawing in air .... Just a thought... you're checking hoses and watnot, the intake manifold could be loose or missing gaskets ! ?!?!
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
Shmed
Posts: 3568
Joined: Wed Dec 15, 2004 2:38 pm
Location: Worcestershire

Re: Car won't idle

Post by Shmed »

It wasn't off when i got the car, and I haven't had it off myself, the thought had crossed my mind though. I'll take a look at that when I have more time, or an assistant with me to keep the engine running while I'm under the car. :thumleft:
JJ
Posts: 3825
Joined: Tue Dec 14, 2004 9:11 am
Location: Stockton-On-Tees

Re: Car won't idle

Post by JJ »

Got a dump valve on it ?? stock ??! after market ??!! I cant remember, but I'm sure theres a take off nozzle from the intercooler pipe that goes from the turbo to the intercooler ( metal ) .. make sure theres a home for that !

A while back, my friend had similar problems with an ST185 - same engine setup... would stall all the time, run rough... we actually found a crack in the intercooler .. could be worth checking the hoses to the intercooler and checking the intercooler itself ??!!

Just a couple of areas that you may or not considered... or briefly glanced over them and assumed they're fine.
|| S256SX Airwerks Powered MR2 Turbo || V10 BMW M5 ||
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