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I was driving home today and my car was running fine, and then i noticed that it was pinging alittle bit, then it got progressively worse. Pretty sure you refer to it as "spark knock" Then it was like I lost all power......spittin and spudderin whenever I had to slow down. I mean it was running really bad.

When I finally got home, pulled the plugs and #1 and 2 looked fine, #3 and 4 looked really white. (running way lean)

Also, when was messing around with it in park, held the rpms to 2-3k and saw alot of white smoke coming out of the tail pipe.

Im not sure if I killed something inside the head or not.

Heres the things I checked.
ECU, replaced with another good one I had.
Sparkplug wires
Sparkplugs
Injectors, and clips
(car has new fuel pump)


I just cant figure out why only those two cylinders are messed up, and why it was a slow progressive problem, not a sudden problem.

If you need a video to help describe I can provide one.

any help is greatful

You might have blown the head gasket. Do a compression test and find out.

_________________
Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd

ahh yes, I didnt think of that maybe the gasket just blew around those 2 cylinders, and thats why it runs halfass with some white smoke coming out of the tail pipe. I will do a test and post up my findings.

anyone know what the compression should be?

Compression numbers vary widely. As long as all the numbers are within 10 of eachother it should be good.

_________________
Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd

well I did a compression check and starting with the first cylinder after the front of the motor (#1 I believe)
1. 0
2. 0
3. 150
4. 160

So I'm thinking that the head gasket broke between cylinders 1 and 2.

You should have 170-180+ PSI in those cylinders, but given time and wear on the rings, it is still a given that 0's are not your best friend at this point. Performing a compression test on an engine that in theory could have enough coolant pissing into the cylinders and leaking down when the car is stopped is not a good idea. Putting a coolant system pressure tester on the coolant reservoir or in our case the rad cap spot, is the best bet. Cranking over a car that is leaking coolant can result in hydro lock which can bend rods, and then you need more than top end work.

Pull the head before too much can happen to the bottom end.

I checked the radiator, and it still had plenty of coolant. Does this mean that if its the head gasket, its a small leak.....at the moment.

Also, the cars got 170K on it. Is it worth changing? or should I say, do you think that the rings will hold out long enough to make it worth my while?

Sounds like your compression is low but do you have an 8V or 12V motor as I believe the 8V was lower compression. I responded to your other thread with regards to pulling the head and what it may cost. IT may be worth your while to put in another complete motor from another member depending upon what you diagnose the problem to be.

Sounds like a blown head gasket. As long as you take out all the spark plugs when doing the compression test, there shouldn't be any chance of hydrolocking. If you do it yourself and know what you're doing, it shouldn't cost you very much.

_________________
Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd