Simple, Car has poor acceleration. press the pedal and the engine revs and little movement.(like a crawl) when I gets around 3500 rpm you feel a boost of acceleration.

Problems- Had the tranny rebuilt-Auto sad.gif torque converter had to be rebuilt.

mods. Header, cai.

The problem was present when I got the car and I thought it was part of the tranny going out. when I got the thing rebuilt the car shifted better but still no accel. Had some more problems with the tranny not working right and found out that the torque converter was bad and had to be rebuilt.

I can make the car accel faster by shifting the gears myself

what do you think is the problem. its a 1999 auto with about 93500 miles on it.

thx

 

I'll probably say what 90% of people here will say.

Check your TPS/MAF.

MAF is expensive so don't just replace that, make sure its pointed the right way, etc. TPS fixed a problem sorta similar to yours for me.

 

I'd say its your automatic transmission thats slowing you down. I've heard that they are a bit sluggish. Others might have some suggestions to help combat this though.

My one suggestion would be to make your car as light as possible. There is a post here, about all the things you can do to make the car lighter.

*Odessy Battery
*Light weight Rims
*Fiberglass or Carbon fiber hood
*Racing seats in the front.
*Remove the rear seats (if possible, not sure how far you want to go with this)
*There's a lot of junk in the engine bay that can be removed to help reduce weight as well
*If you got heavy rubber floor mats, replace with lighter carpet ones, or none at all.
*You could remove the spare, but thats your own call. I personally would leave mine in incase of a flat when I'm in the middle of nowhere.

Here you go, its the DIY for weight reduction on our cars. This will help you out as well.

DIY Weight Reduction

I'd also look into doin some more to the engine. Better exhaust, pulleys, TB, make sure your car gets regular tuneups and has good, fresh oil as well. You can always look into a turbo as well if your budget allows for it.


You may have to make some sacrafices as well. If you got a huge system, then pull that thing out. You'll loose close to 100 lbs. or more depending on how lare your system is. So take those 15's out your trunk!!! laugh.gif

Good luck with it!

 

Could be a lot of things...do you ever smell exhaust fumes for no reason? If so could be a clogged catalytic converter. Sounds weird but when mine clogged the same thing would happen and every so often it would smell like exhaust. Once you get your engine up to a certain RPM there is sufficient pressure to blow by the restriction rather forcefully giving you a retarded amount of acceleration all at once. Like hamhead said, when was the last time the CAI was off? Did the problem start happening real soon after? Check your MAFS. Can you think of anything at all besides the tranny that was removed or installed right before the problem started? If you can make it accelerate faster by manually shifting the automatic then it's probably not the auto just being the sucky auto. I hate not having the time to change out my auto to stick but I never had that big of a problem with it...

 

Sounds like a tranny related problem to me. I would start with warming up the car and checking the tranny fluid level. Also do you have any lights (CEL) illuminated? I'm also thinking that if the car shifts well on its own when you manually put it into gears, that it sounds like the Tranny Position Switch. Right now i'm more along the lines of it being the tranny fluid. check it and get back with us.

 

could be a number of things. if you have a check engine light go get it checked out.

chances are since the tranny was rebuilt it is at fault. do an auto-manual conversion and rid the problem. my auto trans went to 123k until a solenoid got clogged thanks to a transmission flush job. plus me fllooring it for 40k...

i'd say it depends on your luck man.

 

you have clogged cats, before the car is warmed up, when you first drive it it performs well? then after a little driving does it become sluggish? if so when it is acting sluggish throw it in netral and rev it to 6000rpms. if it stops before that or slows down to almost a stop then it is your cat. if it is not that then check your tps, if it says daisung then you should change it to the kiefco one because the daisung TPS has a history of going bad and was recalled.

 

I will check the fluid in the morning. The car has poor accel no matter if its cold or warm. I have no cel so I cant check any codes. Is the Tranny Position Switch the same thing as a tps? I thought that ment throttle position sensor. (Im new to cars so excuse the dumb questions). I do small gas from time to time but I thought it was cuz of the mods I've done to the exhaust system.

Header(took of stock cat to do so)-2.5 piping to 2nd cat-2.5 to glasspack-2.5 piping to magnaflow muffler.

When I bought the car USED it had the poor accel. I thought it was tranny related so I never thought much of it. But when I got the tranny fixed it was still present. If it matters to tell, I had to take the car back to the shop because the torqure converter was sherdding metal. They rebuilt it. Im still under warranty so if its tranny related should I take it back to them and have them fix it??? Im on a very tight budget so swaping out the tranny I just cant do. Plus I owe the parents 2k for the rebuild and they would kill me if I swapped it out.

I really appreciate all the help smile.gif Driving a car that has a problem is killing the fun out of driving 02.gif

 

i would stick with the basics, and check that fluid out first, and if it's not that you could take it back to the guy who rebuilt your transmission and tell them that the problem is still there. The tranny position switch and throttle position switch are two separate switches. the trans. pos. switch tells your pcm what gear you're currently in. it's posible that the drive switch is shorted. i'm throwing out some possibilities, it's hard to tell you what it is without being there.

good luck fing02.gif

 

any updates?