engine dying under braking

[ian7654]

i know this is similar to the "quick question" thread, but my engine has died twice in as many days as i am braking to turn or stop. here's the general situation:

i'm cruising in 5th at 45ish, then brake and push the clutch in. i was lazy so i wasn't downshifting and engine braking as i slowed down, but i didn't think that could do any harm. anyways, i'm braking with the clutch in and all of the sudden the engine cuts out. brake pressure cuts out when the engine does so i am left to roll to a stop, which is not fun. the radio and lights stay on, so i would think it isn't the battery. then again, starting up last night in the cold (florida cold = low 60s maybe) it didn't want to start.

now i'm engine braking in hopes that this will help somehow.

i don't feel comfortable driving it , and would really appreciate any advice you guys have! :SNSign:

 

[Jinx]

Possible vaccum leak. A friend of mine has an older '95 that had similar problems. We found the brakebooster hose was cracked. We replaced it and it helped somewhat (I'm sure she needs a tune-up as well.)

Check all your vaccum connections and hoses. Unmetered air can cause problems.

 

[GoBabyVroommm]

Vaccum line! I went to the track and i couldn't do better then a 13.8 all night. I would hammer it and right when i hit 4k the car started bogging. IT would do it down the whole track.

Went home thought it was my clutch or something. Next day i couldn't start the car. I thought it was my computer, injectors, starter, etc... turned out it was a vaccum line that was behind my motor. It kept gettin cut when i hammered the car on the frame.

 

[ian7654]

yea, i did a search for this problem and everything that came up was 5.0 stuff. where are the vaccum lines in the engine compartment? i'll give that a look see in the morning.

thanks

 

[BlueRuckus]

This happens to me as well, but it started right after i did the exhaust and predator on my car. My guess is that the RPMs are dropping much faster now, so when i don't "engine brake" they drop too quick for the computer to compinsate. They drop right below idle, hence the shut down.

What I do is just put it in 1st or 2nd and just let out the clutch. I jump starts it right back up before i even come to complete stop. I wonder if a proper air/fuel tuning will eliminate this situation.

If it is a vacuum leak from a loose hose, what hose is there near the x-pipe that may have come loose during the install? I would lean more towards the loose hose idea, because it never did it before the install.

 

[bdcardinal]

just to let everyone know, there isnt a vacuum line that goes to teh rbake booster, we have hydroboost, it uses power steering fluid as a booster.

 

[Jinx]

just to let everyone know, there isnt a vacuum line that goes to teh rbake booster, we have hydroboost, it uses power steering fluid as a booster.

Good info. I was not sure about that either, that's why I stated in my post that the situation involved my friends '95.

Ian - the first place I would check for vac leak would be any tubing that comes within range of the EGR tubing off the exhaust manifold. That EGR tube gets real hot and I've seen vac lines come into contact with it and melt.

BlueRuckus - If yours started after the exhaust and tune install, I would start there first. Make sure there are no exhaust leaks. As for your tune, which one did you use? with a combination of possible exhaust leak (in front of the O2 sensors, my guess) and the Predator "performance" tune you may be running to lean.

 

[BullittStangV8]

Check and clean your IAC. Mine was dirty/messed up. Cleaned it up, and it stopped stalling out at idle and when comming to a stop. Been fine since.
Mike

 

[GoBabyVroommm]

I have a 99 4v in my 96. The vacuum line that was cut went into my intake. I'd go look at it but my car is in storage. Sorry i can't be anymore help.

 

[ian7654]

how do you clean the IAC? I'll go check those hoses now...

 

[ian7654]

ah ha. the tube that runs from the air intake tube to the head (EGR?) was very loose on the intake side. I pushed it back in and it seemed to fit snug, but it also seems like it could come out again. Is there some way to secure this tube?

 

[Jinx]

Stainless steel hose clamp (if the hose slides over a metal tube). If not, try using zip ties to hold it to another (non moving) cable.

Edit: Just don't crimp the hose.

 

[ian7654]

i need to get a digital camera for this stuff. it's way easier to show a pic of something than to type about it.

Jinx, they are both plastic/foam tubes i think. i can't believe they are secured in such a half-a$$ fashion.

 

[DTMach1]

ah ha. the tube that runs from the air intake tube to the head (EGR?) was very loose on the intake side. I pushed it back in and it seemed to fit snug, but it also seems like it could come out again. Is there some way to secure this tube?

There are two on GT's right? one should be a breather line for the PCV system which wouldn't really cause your car to stall...the other I can't remember

However if there is a line that goes from your intake itself to the head, that one is a vacuum(PCV) and would cause your car to stall, althought it would be all the time not just on braking.

I would inspect your MAF for loose hose clamps, clean the IAC if you're up to it, check your intake tube for cracks around the hose clamps and ensure the intake tube is securly attatched to the TB...also, if you can get your grubby paws on some electrolyte cleaner, that stuff works magic on MAF sensors.

If everything checks out and nothing seems loose, but your car is still stalling, I'd reinstall your stock airbox/intake tube to see if the stalling goes away.

EDIT: oooh I forgot, one time mine was stalling like that cause the rubber piece between the TB and intake tube was rolled up on the bottom(IE there wasn't a positive seal) so what the hey, check that too.