drft_180sx

Ok heres the situation. The motor acts like its not getting compression for a good 20 minutes, and after that it's fine. Its as if its running in some safe mode, or some sensor is acting weird until its warmed up?

The car barely idles and sometimes dies during this period of time. I had my rotary mechanic look at it yesterday. He revved the crap out of the motor, and eventually while the car was at redline, there was a big pop, the drivers side muffler had popped wide open at the weld on the bottom. The motor was normal after that, and we both came to the conclusion that the muffler was clogged, and that was the cause all along, BUT this morning when i tried to start her up, she was running like crap again.

I check compression (3 even pulses from both rotors), she's getting spark as well. Im not to sure if there is an easy wasy to check the fuel.

Im going to go outside and remove the exhuast right now, to make sure there is no clog there. But if you guys have ever came across this situation, please help me diagnose the problem. Any input is welcome.

Jahan

PS i noticed a slight bit of motor oil on the rear spark plug? But that didnt seem to affect the compression at all? so im not sure if that has anything to do with it.

TwinTurbo_SE7EN

mine did this a couple months ago. it would just randomly fix itself if I kept it running long enough. I have no idea why it did it and no one else knows. 115+ psi on all faces. I thought it might be a stuck seal somewhere...carbon build up maybe.

but mine went away until last night it did it again. I didnt do anything to fix it cause I didnt know what to do. I think it may be a wiring issue, but dont know where to look. sorry I cant help you more.

drft_180sx

Can anyone please help the two of us out? i know you guys would if you knew the answer...im assuming those that read the post did not, so this is just a bump, dont mean to be annoying...my car is being annoying though!


Thanks, i love you guys ;p

JAHAN

gingenhagen

i would guess vacuum leak. And bumps aren't allowed.

drft_180sx

after more inspection of the engine compartment there seems to be some fluid on the firewall on top of the tranny on the passenger side. it might be fuel, but is there any possibility that this could be contributing to the problem that i'm having? if so, how come the car comes back to life after being run for 10 minutes?

Sideways7

iTrader: (7)

If you can see it, it prob isnt fuel. Gas evaporates very quickly. What does it smell like?
I sounds like you have a jacked up cold start system, or something. Look for the things under "runs bad while cold" in the haynes manual.

drft_180sx

but can a bad cold start system make the car run like complete ****? like its on one rotor? does anyone know?

jasmine

When I first read your post, I was thinking "cold start sensor". The short answer to your question is "heck yeah". Especially if you have other problems going on on top of that, which it sounds like you do. Leaky fluids and so on... you need to fix all that stuff. When the engine warms up, a number of things happen (most notably, the seals expand and make a better seal), and most of these things will make the engine run better and possibly mask other problems. Additionally, the cold start sensor backs off and lets the computer work normally. I would say check and replace the cold start sensor and check all it's connections. 95% sure that's the problem.

crookedFC

iTrader: (2)

yea im having the same problem. but mine makes some clanking noise. might be tranny?. but it only happens when it wants to or when the car isnt warmed up.but after driving it for a while the problem seems to go away. any help?.

drft_180sx

we might have different problems, my car isnt very drivable at all until the car is back to normal. It feels like its running on one rotor, which means i have to rev the crap out of the car to get it moving...


UPDATE:

Removed the catback, ended up breaking a bolt on my presilencer....(DOH!! i hate me) same thing, it wasnt the exhuast al along, my mechanic just cost me 400 bones...

Quick question, Black and green connectors are check connectors? correct? Cause by the alternator on the passenger side there is a white connector not connected to anything...should i be worried?

I am soo sorry for clogging up this forum with unorganized threads like this one...please just bear with me.

Jahan

drft_180sx

im sorry guys im a complete idiot. i cant find "cold start sensor" anywhere in the fsm....is it called something else in the fsm maybe? subzero assist? Thanks

Jahan

ddub

Accelerated warmup possibly. If I had the FSM in front of me I could find it, but I'm at school so no go.

I'm pretty sure it's called accelerated warmup. Subzero start assist is DEFINITELY not it.

If you're cold start isn't working properly, warmup will run shitty and not want to idle properly, especially in colder climates. This is what happens when you remove thermowax and ****, or if it's broken. But, that being said, you can tune/adjust your idle to hold its own during the warmup period. It'll idle kinda funky, but it'll work. If you're still having issues after it's warm (temp gauge reaches ~1/4 on s4, or ~1/2 on s5, and oil pressure reaches normal levels) then it's not the accelerated warmup and something else is wrong.

drft_180sx

But the thing is, when i say the car runs shitty, I mean it feels like its running on 1 rotor, and when you press the gas, the tach moves soo slowly, and the exhaust tone is quite different from normal as well....

Any help guys? i swear, im so ready to give up on her.... =*(

Jahan

ddub

Doesn't sound like an accelerated warmup issue, sounds like something else. If it seems like it's running on 1 rotor, that'd be something unrelated.

Start with the normal troubleshooting. Do a compression test when cold and warm, check for fuel to both rotors, check spark, etc.

drft_180sx

Well i already checked spark at the plugs and the coils...good.
Compression i get 3 even pulses of equal magnitude from both rotors when cold...good.

Not too sure how to check for fuel to both rotors? is there any quick test, like a stethescope?

Also, why would the problem be there for 10 minutes or so, and then all of a sudden dissapear?

I figure the way to troubleshoot this is....what things can mess up when cold and start working when warmed up?
(for example, (opposite from my problem) coils usually start ******* up as they get hotter).

any suggestions? im thinking fuel related, but dont know where to start with all the info i have?

Jahan. thanks again everyone.