When the car is cold in the morning and i leave the driveway like a grandma i get a pretty good hesitation when i shift just after letting off the clutch. as soon as i get on her a little it wont do it again. also when i am in fourth gear and i open up the throttle i noticed a slight hesitation in the transition from vacuum to boost. and alot of the time when i come to a stop the rpms drop and the car surges a couple of times. Does anyone have any experiance with this and is there a fix for any of these problems?
I experience the same damn thing when my car is cold.......It hesitates bad but then all of a sudden it just kicks in......even when I baby it to warm up..........Still haven't found a fix for it though
...Oh and I don't think its reflash related because I dont have the reflash and its doin it......
Car is for Sale!Supercharger kit is for sale!
sounds like a MAP sensor, or your o2 sensor is going out.
I just replaced the O2 sensor after the cat, and the Map is new with the kit. I have another Map that i am holding on to. I will plug it in and see what happens.
Could the bypass valve be sticking a little?
As for the car feeling like it's gonna stall when the RPM's drop to idle... I think that's pretty normal depending on conditions. Mine does it pretty rarely, and more often when the AC is on (bigger load on the engine). Computer has to catch that the rpm's have dropped and give it a bit of fuel.
On the way home from work today I plugged in my scan tool and watched the numbers. When the car seems to hesitate the ignition advance gos down to 0 or even -4 degrees then gradually climbs up. whenever it is under 5 degrees of advance it feels like it is hesitating. the map is reading perfect and the O2 sensor is reading normal. I am running the spark plugs that came with the kit gapped at .040. tonight im going to put some rapidfire #5s in and gap them at .035 . The computer is definately retarding the timing for some reason. If anybody has any idea why it would do this please post.
Is there an easy way to tell if the knock sensor is going off?
I unplugged the knock sensor last night on the way to my parents house and it did the excact same thing, which tells me that its not knock. Today at work while i was on break I was checking vac lines and the map and while i was under the supercharger taking off the map i decided to see if the bypass actuator was working. it didnt seem to be opening all the way under vacuum so i moved it back and forth manually. then it seemed to be working properly after that. On the way home it ran perfect and it felt like it had more power and seemed to spool up the boost faster. I hope that was the fix.
by unplugging the knock sensor it will not tell you if that is the problem. when you unplug the knock sensor it goes into a default mode instantly and it will retard timing from idle to full throttle rather than just at higher rpm points... good luck... did you check the o2 sensor in the manifold "or header if you have one"? best of luck to you
listening...
nate
Evolution of Cavyboy-->C22t--> C24na--->c24s/c
1995 Cavalier W/2k1 Engine
GM S/C 13.940@99.78pmh w/2.068 60ft
2.4's have a problem with high oil pressure when u first start it up till it warms up a little.
might want to look into a coolant temp sensor. i know i had this issue with my 96 motor and that seemed to help. maybe
On my scan tool every sensor appears to be functioning properly. I have an old rksport stainless header with the O2 sensor in the #1 primary tube. It has never been changed. I did just replace the other O2 sensor with a bosch. Coolant temp works perfect. tps works perfect.
hmm.. i would stick with the ac delco 02 sensors, i have seen problems with bosch sensors on 2.4's before.
..... could be a TPS.....
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
I am the king of tps troubles, if it were tps, you would have to let your car sit for at least 3 minutes b4 you could even touch the gas. If you tried, it would stall immediately. Your air fuel drops and the car just about stalls unless u take your foot off the gas, then it sky rockets to rich, sits there for a minute and then drops to stoichometeric. And if you reach 4G on the tach without being in boost, it cuts fuel, either in ecelleration or cause you downshifted into it to slow, I guess that would be decelleration, wouldn't it. Wow, I am special. I've been runnin like that for like 3 months, too cold for me to really care. Mine is a bad wire to the ECU, I hope, cause if not I have no idea, I have had 3 sensors in there already. Oh, and it would throw a code immediately. No driving around for 75 miles or whatever, immediately.
good luck
Scott
When I boost, you boost, we boost
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You have been banned from NEJBODY.
You've displayed wayyy too many acts of pushing people to their limits.
It's never cool to tear people down for what they want to do.
NEJBODY is a team. We're not the same as JBO where everyone bashes on eachother.
I'm surprised you show up to our meets after half of the things you say on here.
I am going to have to go with Bad computer.... I had the same thing and i didnt know what it was and i just left it... then when i had my car in the shop for somthing else they said "oh and your computer was shot, this tends to happen on most of these cars, but there is a 130,000km warenty on it" so go get that checked out at a GM dealer ship...
The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno
130,000km? whats that in english? I swear if I threw out my old boosted ecu for no reason I am gonna be annoyed!
Scott
When I boost, you boost, we boost
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You have been banned from NEJBODY.
You've displayed wayyy too many acts of pushing people to their limits.
It's never cool to tear people down for what they want to do.
NEJBODY is a team. We're not the same as JBO where everyone bashes on eachother.
I'm surprised you show up to our meets after half of the things you say on here.
RaGiN Z wrote:130,000km? whats that in english? I swear if I threw out my old boosted ecu for no reason I am gonna be annoyed!
Scott
lol in some foren language that would be 80,782miles i think they call it? ahahaha
but even if you threw it out and your still under that milage.. go into a GM dealer and ask them to test it... because i had the same thing happen to me and i check every thing.. the dealer ship spent like 15hr working trying to find it and finally came up with bad computer.... and i didnt have to pay a cent sine they said they have a 130,000km (80,782mile) warenty on them...
The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno
