Random misfires on startup

steve.21

New Member
Hey everyone. My car has been having misfire only on startup. It does not matter if the engine is warm or cold. When I start up the car one of the following things will happen
Starts perfectly fine no problems (20% of the time)
Starts up and has a rough idle for about 30 sec then the down cylinder/s start to work throwing no codes (40%)
Starts up and has a rough idle for about 30 sec then the down cylinder/s start to work throwing codes cylinder 1 and/or 2, 4.. Never 3 for some reason. With a random misfire code... Forgot the number (20%)
Starts up and throws codes(same codes) and stays until I hit the gas and the rpm's go above 1500. Then runs fine. (15%)
Takes forever to start followed by only one cylinder firing... You can hear and feel it. Then stalls throwing no codes. (5%)

Only mod I have is a new short ram(problem existed before I got it)
I have replaced the plugs, wires, distributer cap rotor.
Cleaned the iacv, distributer cap, throttle body.
The inside of the dizzy cap looks fine and the spark plugs are dry.
When I got my car smogged my ignition timing says 11btdc. Don't know what that means. Could the problem be in the fuel injectors, tps, or any other sensor thing. I don't have access to a engine hoist or anything fancy.
Any help will be greatly appreciated and I will try to respond as fast as possible to anyone.
Edit: it is a 97 lx auto transmission.
 

Trekk

New Member
Registered VIP
I would do a compression test just to rule that out first. How does the car run, once it is on and runnng?

Normally what happens when you get a misfire is this. In simple terms, the ecu knows how fast the crank is moving, durring cylinder firing, it speeds up for a split second then slows back down. When a missfire is detected it is because the ecu didnt see that speed increase pattern.
 

SeeOurWrecks

New Member
5+ Year Member
You said your timing was 11°btc? Check what it's supposed to be, i think it's closer to 15

Tapatalk rocks!
 

steve.21

New Member
SeeOurWrecks said:
You said your timing was 11°btc? Check what it's supposed to be, i think it's closer to 15

Tapatalk rocks!
Click to expand...
Yeah, I have heard fifteen degrees before but where it is now is still in reasonable range according to a mechanic I talked to.
And update... Sorta... I fired it up and stood outside the car for a longer time I would have. There was no smoke.... But then after the misfires all stopped, a few sec. Later, it started to smoke like the cars do on a cold day.(it's about 78 outside) The reason I did not see this before is I would look for the smoke during the misfires or a little after the smoke stopped(from what I saw). And the smoke was white. don't want to rule anything out yet, but do you think that a leaky head gasket could cause the misfires until the antifreeze off.. Or it's smoking like a car would on a cold day. I'm working on getting another video of it. And about how much will the head gasket repair cost. I dont have a lot of money and it would have to wait till at least the 2nd of August.
Would autozone have the compression test in the loan a tool program?
 

Trekk

New Member
Registered VIP
If you are driving it I would suggest putting a fuel additive in the tank. I think the techron stuff works the best. It won't hurt and overtime it will clean the fuel system anyways which is never a bad thing.
A simple test you can do with a long screw driver is get the car running and then place the screwdriver on the injectors one by one and listen to them with your ear on the handle. You should hear a sharp clicking from each.

To be honest to really pin point w/o guessing you would need to check spark, compression, fuel pressure, timing.
 

steve.21

New Member
Got the compression tester thing. Results will be up in a few hours when I do it. Thanks for the tip of the screwdriver injector check. Any way of testing the fuel pressure? And I'll get the additives when I return the tester. The guy at autozone said that I should seafoam it, or that the ecu is bad. Thoughts on those?
 

steve.21

New Member
Well... I started on cylinder 4 and went backwards.. #4 was about 130. #3.... That's a fun story... The plug was wet. Look down and the whole piston was wet. Unknown compression because that damn hose exploded. #2 the cylinder looked damp. And #1 looked like it was covered in carbon......... f**k...
But the screwdriver injector test sounded good.
 

steve.21

New Member
Thoughts about the stuff you pour into the radiator that's suppose to seal up the leaks as a temp repair?
 

steve.21

New Member
For sure it's the head gasket.... But a small leak. Had a shop run a compression test and got 160 in each cylinder. But on the lockdown test with the blue thing in the tube above the radiator and in 2 pumps it was green. Glad I could put this up for anyone else in the future with this problem.. Thanks for all your time with this
 
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