Acceleration weirdness

[Mullet]

I've been having a problem with WOT since i got my sho 2 months ago. I took it into the shop last week to have them check it out and they said i needed a new fuel pump. 400 bones later, i get my carback today and guess what, still stutters at wide open throttle.
I did a little test of my own and from a rolling 5mph start in first gear i floored it and kept it floored. Rpms slowly crept up to 4 grand when i got the shock of my life, the car starting pulling harder than ever. I did this a few more times and sure enough, my car is only getting power at WOT when the runners open up. My question is what do you guys think this could be? Any help is much appreciated and i thank in advance.

 

[Mr Anonymous]

Have you checked for any codes? That would be the first place to start. Could be a TPS problem. Heck, it could be a number of things. Start by checking the codes (there are FAQ's on this at www.shotimes.com as well as at http://dalidesign.com/hbook/eectest.html)

<small>[ October 24, 2002, 09:25 PM: Message edited by: SHOooo ]</small>

 

[Mullet]

The guy at the shop said it wasnt putting out any codes, he also checked the cats and said they were not clogged. All my sensors are "within limits" so im basicly stuck.

 

[AutoSHO]

Mullet:
The guy at the shop said it wasnt putting out any codes, he also checked the cats and said they were not clogged. All my sensors are "within limits" so im basicly stuck.

My car does this, and it is because my MAF sensor is bad. It reads too lean, but above certain RPM's it starts to read closer to tolerance. I also have an A/F gauge that confirms this. Try cleaning or swapping your MAF sensor with one out of another car. Good Luck!

 

[sdpatt]

...or your secondaries aren't closing. That would allow the 4000+ range to be normal, but the power output below 4000 rpm is gutless. The secondaries are closed by vacuum. Ensure the vacuum lines are connected to teh accumulator and solenoid and the electrical connector is attached to the solenoid. All of this is onthe back of the rear intake plenum. However, that wouldn't cause a stumble or misfire. You may want to pull a few plug boots and look into the plug wells. Check for oil in there. If you find it, you probably found your stumble.

 

[Mullet]

i've disconnected the vaccum lines before just to see what its like if its open all the time. It ran alright slower than normal, plus i can hear them open up at 4grand so i dont think thats it, im gonna see if i can find me a maf and hope that does the trick. Thanks for the help and suggestions, of anyone has anymore lemme know

 

[sdpatt]

Don't hope. Determine what is wrong and fix it. You still have some more diagnostics to do. Why throw money at something that may not be the problem? The mass air flow sensor will not cause a misfire. Check those plug wells for oil. How old are your spark plug wires? If they are more than 6 years or 120,000 miles old, they are long overdue for replacement. Have you verified that the secondaries are closing by observation rather than the sound? This is important.

85% of fixing something is finding out what is wrong.

 

[Mullet]

Yes i have verified that the secondaries do open and close properly.My car is a 95mtx with 96,000 miles. I just replaced the plugs but i should probbly do the wires too.

I have another question on what i should do about this "shop" that i went to. First of all my complaint on the car was that it stumbled at low rpm, so they put in a new fuel pump and said "good as new" i start the car for the first time and i hear one **** of a squeal, its coming from the driver side rear tire, i assume its the fuel pump. I take it in stride and decide to see if they fix the problem like they said, nope it has exactly the same symptoms which i paid $450 to fix. What should i do about this shop? take it back and have them fix it? i'm only 17 and dont have much experience in dealing with things like this and any help would be great.

p.s. when i replaced the plugs there was oil in 2 of the wells, but would this explain the almost no acceleration at wot at low rpm but when the secondaries open an insane boost?

 

[flosho]

Take it back and tell them you want one **** of a deal to FIX the problem, because the Fuel pump sure aint the solution... Be polite about it though, and show respect, because if a 17 year old comes in cussing and ******** they aren't gonna give you any respect.