Desperately seeking help

[chip]

Hi everyone,

I bought an '85 T-Type a while back and just can't get it running right. The car was high milage, so I bought it to restore. It seems to run very well until I hit 1/4 throttle, then it just boggs down. The boost maxes out at 10 lbs and it is just not at all fast past 1/4 throttle. It really wants to go but the power just stops coming on. Below is a list of what I have done with the car. If anyone has any ideas what might be causing this, please let me know.

Rebuilt engine (1500 miles ago)
new TE-33 turbo
new Walbro 340 Fuel Pump/hotwire kit
dual 2 1/2" Hooker exhaust/mufflers
new 36 lb Bosch injectors and fuel pressure regulator
test pipe
3" up pipe (hopefully 3" downpipe soon)
new TPS sensor
cleaned out throttle body
9" K&N, 160 degree thermostat, Jay Carter chip
new plugs, wires, etc.

I checked the following:
no trouble codes on GM reader
ignition coil - OK
fuel pressure - OK
vacuum - OK
volts, temp, oil pressure - OK
TV cable - OK

Thanks for the help, I really appreciate it.

Chip

 

[dave84gn]

Hey chip. Looks like you're new to the board: Welcome! Great place, we'll get ya running right.

I'm not yet a diagnosis expert so I won't throw out any of my theories (i'll leave that to the more experienced) but I will say this:

Get a scantool! You'll probably hear this after every one of your posts until you get one! A scantool (see www.gnttype.org for more info on scantools and everything about turbo buicks) will give you an idea of what's going on with the car -- particularly sensor wise.

I'd bet no one who has purchased a scantool has EVER regretted it. Heck, mine isn't totally working with my car *yet* and I'm still glad I bought it!

Good luck.

Dave

 

[SLOW_85]

TPS? 10 #'s boost isn't much. Could be running too rich.
I would check the TPS first. How much FP you running?

 

[chip]

Thanks for the help. I tested the TPS, its OK. I have the fuel pressure set at around 44 lbs. Also, it has a new fuel filter. I will try to get a hold of a scan tool soon.

Chip

 

[SLOW_85]

Is that 44#'s FP static? Kinda high either way.
Running to rich will cause it to bog.
Like I said 10#'s of boost isn't even stock boost.
Might try lowering FP or raising the boost.
Outside chance it could be a bad o2 sensor.

 

[chip]

It's great that so many people have responded to my post, I really appreciate your ideas.

I finally got a scan tool on that bad boy. I adjusted the fuel pressure to around 40 psi, checked engine vacuum (16 psi at idle). Also, I put in a new oxygen sensor in order to eliminate my old one as a possible problem. I borrowed a friend's computer and chip to ensure that the computer is not the problem. Also, my chip DOES match the injectors.

I took it for a drive and it was really knocking. I am running 92 octane fuel with octane booster, and only getting 10 lbs boost but the knock read up to around 36 when I got on it. I know that is WAY too high and am suspecting that my knock sensor may be bad. Also, my plugs, which are pretty new, were a little black on the tips.

So, other than the knock sensor, I am running out of ideas.
Anybody have any suggestions.

Thanks,

Chip

 

[Buick From Hell]

36° retard at 10psi, I'll bet a set of strap screw covers one of two (or both?) things is to blame:

1) Does the car still have the cat convertor? If so, it may be partially plugged up! (they're famous for this!)

2) CHECK YOUR CAM SENSOR SETTING! These engines WILL start and *seem* to run fine if the setting is too far advanced! I had this happen when I changed my timing gears & chain! It drove exactly like you're describing too!

As for 10psi boost, when I finally got a boost gauge for mine, I found I was only running 8 psi! Anyway, it's an easy fix if you have an adjustable wastegate rod! (Just don't mess with it until you've figure out the first problem!)

Here's a link to explain how to check the cam sensor adjustment:
Cam Sensor
Adjustment

 

[chip]

I checked the cam sensor setting, its OK.

Also, I have no cat, straight pipe only. But thanks for the help.

Chip

 

[cool 84]

You might want to put some racegas in it and verify it's not false knock. Run it at full boost with the good gas and see if the retard goes down. If it stays the same it's probably false knock. That much retard at such low boost is pretty hard to get. You are running a street chip, right? What were your 02 volts during the run? Also check alternator voltage. Even at 12.8 volts, mine would detonate horribly. You really need to have at least 13.5. As a last resort, make sure your turbo isn't leaking oil into the intake. Oil will severely lower the octane. What kind of plugs are you using?

 

[Dave85]

This has nothing to do with drivability problems but you could be getting false knock form bad engine mounts. Just an idea.

Dave85

 

[SLOW_85]

Another thought alternator belt slipping. Had this prob before.