so i sold my Z24 to my little sister a few months ago and today she called me in a panic because the car was accelerating on its own when she drove home from work. it was revving to 3000rpm while she had her foot stomped on the brake. Can anyone give me some clues on what this may be and what to look for to fix it? it is apparently the first time it has done it.
The man who smiles when things go wrong has thought of someone to blame it on. - Robert Bloch
Vacuum leak.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
vacuum leak where? what hose would be leaking and what can i do to fix it?
The man who smiles when things go wrong has thought of someone to blame it on. - Robert Bloch
Any vac hose or gasket after the TB and before the valves can cause a leak. Could also be a stuck throttle cable. My guess is that the hose to the MAP is broken.
My money is on MAP hose, or floor mat. But more likely MAP hose. It gets very brittle over time. Just look at the front of the black plastic intake manifold. There's a small hose, just a couple inches long, that connects the map sensor, mounted to a throttle body stud, to a nipple on the manifold. Replace it. Check other hoses connected to the TB as well.
"Only two things are infinite, the universe and human stupidity, and I'm not sure about
the former." - Albert Einstein
I'm surprised no one brought this up. A TPS will also throw a code and make the car drive on it's own. Literally, it will make the car accelerate or even run forward by itself in some cases, as long as the car is out of Park. Have her pull that Sensor first just to make sure it's not bad. If the Sensor is fine, then have her check for Compression leaks, like everyone else said. Hope all works out for her, and no one gets hurt.
2000 Teal Coupe, 2200 SFI LN2. 186k and still running strong. It may be "just" a Cavalier, but it's mine.
Mine was doing it but not reving that high...turns outto be
replaced the map sensor vacuum hose ,was dry rotten
replaced intake manifold gasket ,was leaking in cilinder 2 and 3
Replaced fuel injectors O rings, the lower ones where leaking, but replaced all just to be safe.
Mine is a 99 z24 also,low miles
I bough 2 bottles of carburator cleaner and started spraying all suspected hoses and gasket with the engine running at idle,
Every time I sprayed the intake and injectors area. The engine stumbled and die on me,so I knew the leak was huge.
Did it my self, spent around $40 on parts, around 4 hours labor time,3 bottles of Carb and parts cleaner(cleaned intake manifold,trottle body and intake ports)
And added a bottle off sea foam.
No more vacum leaks on my car...at least on the engine side
