Galant vr4 cuts out after a few minutes of idling

[barreh13a]

Hi, Having a very weird issue after my 96 manual galant vr4 car has sat for a few months.

My galant Vr4 has been off the road for about a year, needed a new clutch and a bunch of other things. Recently finally did the clutch (PITA) on the garage floor, drove it around the block for a couple minutes, was all good, had never had the car leave me stranded. Painted the brakes the other week and went for another drive to scrub off any paint that got on the brake surface of the rotors, drove up and down the street, turned around, headed home and while cruising the car cut out. Luckily could roll back into the driveway, but the car didn't start again. cranked over fine, all accessories worked, but no go.

Left it for 10 minutes, started again but died straight away. No splutter, just died like turning off the car would do. I thought this might be immobiliser related so spent last night pulling that out and repairing all the wiring. turned the car on and let idle, idles for about 3 minutes and then died again, no splutter. Thought it might be turbo timer, so removed that and same issue.

Spent today trying with the maf unplugged, vacuum lines unplugged, reset the ecu by disconecting the battery. Checked for any codes by bridging the diagnostic plug. There's nothing obvious. There was some moisture on the inside of the firewall when i was poking around so i pulled the ecu out to see if there was anything obviously damaged on the board, all looks pretty normal.

anyone had similar issues or ideas to check? would a faulty ifs still allow the car to run for a bit before dying?
are there any failsafes in the ecu that would cut the engine for any reason?

 

[mezje]

Got a spare Crank Angle Sensor? Also is your IFS bypassed?

 

[Baba Galant]

I'd go with immobiliser on this one. When mine started to go it was hard to start or wouldn't start. If course the bastard failed while I was on the road...
The onboard relays for cutting the ignition power failed.
It shouldn't be too hard to just connect the ignition wires going to and from the ignition plug to test this without removing the immobilizer.

 

[kc427]

I'd go with immobiliser on this one. When mine started to go it was hard to start or wouldn't start. If course the bastard failed while I was on the road...
The onboard relays for cutting the ignition power failed.
It shouldn't be too hard to just connect the ignition wires going to and from the ignition plug to test this without removing the immobilizer.

I agree with you. My immobiliser got failure after around 5,6 years. I only had starter kill, so, the starter wouldn't start at all quite frequently. I didn't notice the immobiliser failure after I changed 2 rebuild starters, and then my friend suggested me to bypass it and tested. After bypassing the immobiliser, starter worked like a charm. Yes, as you said, the onboard relays could be low quality that cannot last long.

 

[barreh13a]

I’ve already removed the aftermarket immobiliser and fixed the wiring, there’s no immobiliser now, leaning to a cam or crank sensor, but it’s weird that it will still start and run for a bit, others with cam or crank issues didn’t want to start at all. day off tomorrow so gonna do a bunch of different tests

 

[barreh13a]

Got a spare Crank Angle Sensor? Also is your IFS bypassed?

No spare sensors, might have to see if anyone in sa has some

Is it just bridging the pins like in the ifs guide?

 

[mezje]

No spare sensors, might have to see if anyone in sa has some

Is it just bridging the pins like in the ifs guide?

Indeed it is.

 

[kc427]

How about fuel related issue? Eg, fuel filter cogging? Fuel pressure sensor failure? Fuel pump? Fuel pump relay?

 

[Baba Galant]

Did you end up bridging pins 3 and 4 on the IFS cable?
How is the wiring harness around the firewall? I had an intermittent cut out once when the tacho signal inspection plug shorted to the metal hangers on the firewall.
The IFS itself could be failing and the tacho signal shorting.
I would unplug the ifs, short the 2 wires temporarily(3 and 4) and see if it stays running. You won't have a tacho signal but that's fine until you bypass it with an IFS delete cable.

 

[barreh13a]

Did you end up bridging pins 3 and 4 on the IFS cable?
How is the wiring harness around the firewall? I had an intermittent cut out once when the tacho signal inspection plug shorted to the metal hangers on the firewall.
The IFS itself could be failing and the tacho signal shorting.
I would unplug the ifs, short the 2 wires temporarily(3 and 4) and see if it stays running. You won't have a tacho signal but that's fine until you bypass it with an IFS delete cable.

Just tried bridging the pins, made no difference other than no tacho signal, I also get no spark after the engine shuts off and I try to start it again, it cranks over but no spark

The first time today that it died it wasn’t a sudden shut off, the rpm dropped slowly to the point where it had a really lumpy idle, started to backfire a bit, then die

Next on the list is Iac, Cam and crank sensor, and to check fuel delivery

 

[barreh13a]

started the car after a couple hours, and then unplugged isc, idle stayed constant 1500rpm~ and slowly climbed to about 1700 before the car shutoff again, this time with no splutter, leaning towards ecu but can only do so much without evoscan or mut ii tool

 

[Baba Galant]

Have you tried starting it with the MAF unplugged?

 

[barreh13a]

Have you tried starting it with the MAF unplugged?

yeah, threw a engine light and ran with constant idle before dying

 

[barreh13a]

also does anyone know who i should go to for diagnostic if i can't figure out this issue myself in SA?

 

[kc427]

Just tried bridging the pins, made no difference other than no tacho signal, I also get no spark after the engine shuts off and I try to start it again, it cranks over but no spark

The first time today that it died it wasn’t a sudden shut off, the rpm dropped slowly to the point where it had a really lumpy idle, started to backfire a bit, then die

Next on the list is Iac, Cam and crank sensor, and to check fuel delivery

It might be good to know that no spark after the engine shut off, at least most likely it is not related to fuel system stuffs. If no spark, assuming no spark on all three coils, not just particular one coil you tested. If say, one coil failure after it is hot enough, 6 cyc -> 4 cyc, probably cannot start again, so maybe can check all three coils with no spark after engine shut off. If no spark for all three coils, first check could be the IFS, and as @Baba Galant said bridging pin 3 and 4 to bypass the IFS, but you said you did that already. Maybe you can also check each of the coil pin 3, and see any voltage, maybe 12v or 5v when cranking. If no voltage at all three coils, check back on the ECU side, C-31 pin 10,11,23, and again to see any voltage when cranking. Normal, should have some voltage when cranking. If no voltage at all, that means ECU not sending any signal out at all, and need to check "upward" and check what cause ECU sending no signal to coils.

I also suggest you to check the common ground as well, that's the ground point near the ABS pump, wiper motor. If rusting or bad grounding, it might also be a problem. Also check there is good ground on each of the coil pin 2.

 

[BCX]

What area in Adelaide are you?

Happy to lend a hand.

 

[Baba Galant]

I was curious to know if the shorting of pins 3 &4 was done while the IFS was unplugged. I know for a fact that if the tacho signal grounds the car will cut out and not start.

 

[barreh13a]

What area in Adelaide are you?

Happy to lend a hand.

I’m in mount barker, waiting on cam sensor to arrive and try that out,

weird tho cos the car splutters and doesn’t start with the current cam sensor unplugged, and definitively doesn’t even try to start with the crank sensor unplugged, but plug them back in and the car fires up like there’s no issue

This is what gets me, the car runs perfectly, revs easily, and idles fine for the first minute or two during the first start after sitting for a couple hours, but then won’t start afterwards, so frustrating

I was curious to know if the shorting of pins 3 &4 was done while the IFS was unplugged. I know for a fact that if the tacho signal grounds the car will cut out and not start.

Yeah, did that too, no tacho, car still ran perfectly till it died after minute or two as it has been doing before

 

[Baba Galant]

This one's a doozy! I did a job on someones magna once with this but it was a bad connection to the thermostat temp sensor. It was buggered and died on the wiggle test.

 

[barreh13a]

This one's a doozy! I did a job on someones magna once with this but it was a bad connection to the thermostat temp sensor. It was buggered and died on the wiggle test.

I’m up for trying anything so will suss that out too