19 replies to this topic

[mico]

I started the car this morning and it all started fine but when i pulled off the driveway it just wont accelerate and it feels like it's dying.Very rough idle. I drove it back to the driveway somehow. It was all fine last night when i drove it but all of a sudden this thing just happened overnight. Anyway i checked the leads resistance, ok. i thought it was the coils so i replaced it with a second hand one, same thing. checked the timing, all marks line up, spark plugs, ok. So i tried pulling out the leads one by one from the left if facing the car. First one when i pulled it out it feels like it's dying same with the second one from the left. But when i pulled out the third and fourth one, nothing happened, car was still running so could these last two cyinders not working? Please help..

[BMGTZ]

what car?

[Entaran]

pull your ECU out and look for capacitor burn

[bazeng]

Or check your ignition module (transistor unit). They can fail at times.

I've also seen on a mates GSR (VR4 Motor).
The little black rectangle unit in this pic failed.



It was a brand new unit also!

[GVR40]

sounds like number 1 & 2 aren't firing. so eliminate the basics first...
1. does it have spark, check plugs and leads, if still no spark check the coil pack
2. does it have compression...you could have a blown head gasket between number 1 & 2.
3. does it have fuel
4. does it have air

[mico]

thanks guys, it a 88 j spec vr4. I've checked the spark plugs, leads, timing, ecu , replaced coils, all ok as far as i know, the only thing i haven't done yet is a compression test, will get or borrow a compression tester today. i cant really think of anything else, just happened overnight. everything was running ok the night before. I also swapped the two injectors thought the other two were blocked but still the same.

[Entaran]

The coil fires in wasted spark, it won't be anything to do with the ignition system if it's 1&2. as it fires 1&4 and 2&3 together. If you'd lost one of those pairs it would be ignition.

[mico]

could it be the cylinder head gasket?

[bazeng]

Try the basics first mate.
IGNITION/FUEL.

Most likely IGNITION if its 2 cydliners.

[Entaran]

If it's a HG, a comp test will show it as the cylinders will have zero. It may also be a burnt valve on one or both cylinders if the comp test shows a zero.

Compression test time

[omad]

it's not something silly like afm plug came off or ic piping doing the same ?

also got datalogging? Any fault codes?

[mico]

checked all connections (afm), leads ,cleaned the plugs , all ok. It cant be data logged cause there's no socket for data logging( 88 jspec). Car still starts but engine shakes heaps on idle.. and sound like a two stroke engine. Still haven't done a compression test. Will that more likely to indicate a blown head gasket?

[GVR40]

it's looking more and more like a head gasket to me

[mico]

I got the car towed at mike dale's workshop today, he diagnosed it with a blown head gasket between 1,2 cylinders. hopefully nothing major when he pulls it out.

[Qik-1.8]

id say you could have a warped head

[Entaran]

It'll only warp if it overheats.

63's never warp when they blow unless they cook.

A comp test would've shown up the HG straight away.

[mico]

The car didn't over heat, just started it and suddenly hesitated when it was running ok the day before. Hopefully not too much damage on the head.

[blackvr]

It'll only warp if it overheats.

63's never warp when they blow unless they cook.

A comp test would've shown up the HG straight away.

I could hear it when Mico reversed it away from the tow truck... it was "pinging " heavily as the flame in one cylinder lit up the one next to it ( at the wrong time !!). Disabling the spark, and a quick "audio comp test " almost convinced me that I was wasting my timing getting my comp tester out... but I did anyway... and it went straight out the companion cylinder. Oh well off comes the head.

Guess I will find out tomorrow morning how bad it is. Its strange that it suddenly went, as usually they happen over a small period of time. Just hope for Mico's sake the head hasnt gone soft between the cyl 1 and 2.

Cheers Mike

[MDK87]

I could hear it when Mico reversed it away from the tow truck... it was "pinging " heavily as the flame in one cylinder lit up the one next to it ( at the wrong time !!). Disabling the spark, and a quick "audio comp test " almost convinced me that I was wasting my timing getting my comp tester out

Geez you're a smart man Mike. I won't even ask... haha

[blackvr]

yeah... the cheaparse permaseal headgasket had blown clean out, as suspected... Head should come up ok with a haircut .. and luckily passed the hardness test. Mico is "reasonably" lucky.. it could have been much worse !

Mike