help!!

[ace-135]

1986 T-Type WH-1 pkg. 47,500 miles...stock except for 6 position chip and air intake. Was running super until 3 weeks ago and started to stumble on acceleration. It's been at 2 different shops and i'm out 500.00 plus!!! It's still not right. I've replaced the following: coil, TPS, mass air flow, fuel pump, o2 sensor, fuel pump hot wire kit(thanks to cottons) and now they say it's 90% but not quite right!!!! Once it warms up they say it okay but still some hesitation when it's first run. All numbers look good ...fuel air mix, volts, fuel pressure, etc... any suggestions? It's a stab in the dark but hey....what can I loose now ...another week without the car??!!

[Night Train]

Did you try going back to the stock chip? Whose 6 position chip do you have? What else is on the car for add-ons?

[waGoN]

Did anything change around the time that you started having the problems?
These shops that you brought it to....are they turbo Buick shops? It makes a difference,
Hmmm, let's see....These parts, they were installed after you started having problems, right?
The new parts may make it more difficult to trouble shoot.
TPS, was it just thrown on, or was it set correctly? Probably not the problem.
Chip....does it have a stock setting? Does it act up when running all 6 settings?
O2 sensor, probably not the problem.
Fuel pump hot wire, a good addition, but again, probably not the problem. Do you have a fuel pressure gauge? Do you know what the fuel pressure is set at? Does it rise with boost? Original pump?
Mass Air Flow, where did you get the replacement? The remans can be a crap shoot.
Has anyone checked/adjusted the cam sensor?
Any leaks in the intake hose?
Where are you located?

[JCotton1]

Ya... what they said!! Need more info, like what exactly happened when it began to act up. Running perfect and stumbling has to have an event in between... Thanks Bri, Bob..

[ace-135]

First....the car has the "Ultrachip" 103041 is the number on the installation instructions. No there are no turbo buick shops up here in Bangor, ME. I drove the car yesterday and it's about 80%. It pulls well but at open throttle it seems to be cut out as though it needs more fuel. This all started after I put a new O2 sensor on it. Then came the fuel pump, then the hotwire kit, then the mass air flow, then the coil, lastly the TPS. All seem to make the car run a little better each time. To the point now where it is running well except at wide open throttle. They guys say it's running lean when fuel demand is increased...ie wide open throttle. They are coming across some baffoonary that the first garage had done..(running the hot wire kit to close too the exhaust and melting) They reconnected the original relay and it's actually getting more fuel pressure that with the hotwire kit. I'm thinking that maybe the fuel pump is still the problem...I don't know what kind of pump they put it!! But it seems that it's not enough pressure at full throttle causing a lean condition and the subsequent cutting out at wide open throttle. Just have a feeling that the 1st place had NO DAMN IDEA what they are doing. The guys that have it now have all the books and all the tools to measure this and that...fuel pressure and volts and what have you... Thanks for the response guys any ideas would be appreciated!! Also...like I said before...other than the chip and the air intake....the car is stock.. thanks

[Mike_g]

You really should have a scanmaster so you could monitor the car/ read codes and values like the TPS they threw at the car.
I dont like the fact that you have no Idea what the shops used for parts. IMHO some replacement parts do not measure up to GM. (The MAF and Coil in your case)
Did they replace the control module when they did the coil ?

[waGoN]

Originally Posted by ace-135

..other than the chip and the air intake....the car is stock..

Does this mean that the fuel pressure regulator is still stock? If so, then that is probably your problem.
The stock regulator is set for something like 30#. I don't even know for sure.
After market chips usually require that you run any where from 42-45 static as a starting point.
If you are running 25 % less fuel, it won't be that noticeable at part throttle, but when you get into WOT, you need that fuel, and with a stock regulator you won't get it.