HELP!!! I've tried EVERYTHING and my car still sucks

[chip]

Hi everyone,

I bought an 85 T-type awhile back to fix up. I knew it had some problems but I intended to spend some money and get it running right. However, everytime I think I find the problem I'm wrong and it still runs like crap. I think I have checked everything and replaced all the bad parts and I'm running out of ideas. The car just seems to have no power. I'ts only making 10 psi boost and the best I can run 0-60 is 10 seconds, exceedingly slow. It just doesn't have the power off the line. Below is all that I've done. Maybe someone on the forum will have an idea of what could be wrong. Thanks!


Rebuilt engine (1500 miles ago)
new TE-33 turbo with adjustable wastegate
Bosch 36# fuel injectors, Jay Carter chip to match injectors
new Walbro 340 Fuel Pump/hotwire kit
dual 2 1/2" Hooker exhaust/mufflers - no cat
new 36 lb Bosch injectors and fuel pressure regulator
3" up pipe (hopefully 3" downpipe soon)
new TPS sensor (adjusted to .42 V idle, 4.82 V WOT)
cleaned out throttle body
9" K&N, 160 degree thermostat
new plugs, wires, etc.
new TPS sensor (adjusted to .42 V idle, 4.82 V WOT)
new knock sensor
new cam sensor


I checked the following with EZ-Link on a 5 minute hard drive:
no trouble codes on GM reader
O2 volts 500 - 800
knock - totaled 52
temperature - max at 165 degrees

Tested:
ignition coil with Casper's tester - OK
fuel pressure - OK (about 38 psi with vacuum line on)
vacuum - OK (around 18 psi)
volts, temp, oil pressure - OK
TV cable - OK
swapped ECM with friend's working ECM - no improvement in performance so I think the ECM is OK
tried different chip, also no improvement.

I suspected that the engine work might have been shoddy so I checked the timing chain and looked at the rods/pistons. All seemed OK.

I am completely out of ideas. I'm starting to think the car is cursed! If anyone has any questions or ideas, please let me know. Thanks.

Chip

 

[Way2QWK]

Did you get a chip burned for that combo?

 

[1984grandnat]

Be sure to double-check that coil pack!!!! I had a similar problem when I first bought my car. I could only hit about 3 or 4 psi boost. Any more than that, and the car would backfire through the intake, and sputter until I let off of it. Also, when slowing down from 80 mph, would backfire and let out a huge puff of black smoke. Tried replacing literally ALL sensors, and finally checked the coil pack to find that the center coil was almost completely dead! After replacement, I could run 10 to 12 psi boost and car drove MUCH better.

I'd bet money this is your problem, especially if you haven't tested it! If you don't know how to test it, let me know and I'll tell you.

 

[Men in Black]

Check for exhaust leaks at all the joints including your new up-pipe, usually a major reason for spool up problems. Did you put the stud in the turbo outlet going into the manifold?

 

[REDS HOT AIR]

knock totaled 52 ?

at that point you would here it pinging ... do you?

if not check for something hitting the knock sensor if nothing then if you dont hear any knock un plug the knock sensor and go for a ride if you here it ping at all get out of it.

before i pulled my hotair motor out i ran most all the time with it unpluged but i didnt really care if it broke.

or just get a new knock sensor and i wrap mine with teflon tape on the threads and dont over tighten it in the block.

 

[Waco84GN]

Just an idea

When I first got my car, I took it to the track and the thing was a slow slug!!!! I started going through the different engine systems and finally found my problem.

The catayletic conveter had basically just fell apart inside and had the exhaust about 95% blocked off. The car would not run worth a dang and wouldn't build past 8 lbs. of boost. I would look into this if you havent because the exhaust system of a car must be able to handle the pressurized air before you can produce any.

Just my thoughts.

Jerry Berger

 

[GNeric]

My 84 T acted the exact same way when I got it. Took about 1 week to find out the previous owner had a replacement torque converter installed. It would stall to about 1300 and ran like a N/A 3.8. I got ahold of an unmolested D5 and later a 2800 and now she runs like a tight wound top.

 

[Buick From Hell]

I caught the "knock totalled 52" also!


CAM SENSOR!!!!!!!!!!!!!!!!!!!!!!!

(I'll bet a buck it's set too far advanced)

 

[REDS HOT AIR]

hey BFH ....we catch the only thing up there on the list thats way off and nobody listens...oh well.

funny they wont listen to the ones that have been fast with much much less parts....

 

[crazygn]

I don't know if the cat would give you any knock but i would go with BFH cam sensors are a pain. Make sure the window is facing the drivers side of the car and set it again . Mine ran really bad with it out a little to , .

 

[chip]

Thanks for the help.

The car has no cat so that's not a problem. I may not have set the cam sensor right. I did the voltage test and could only get it down to 8 V, I think its supposed to be close to 0. I'm not sure about the torque converter, how can I test that?

It has a new fuel filter so that's OK as well. The chip was not burned specifically for that combo but was burned for the 36 # injectors.

I'm quite sure the coil pack is OK, I used Casper's tester and it looked like it was working very well.

All of you, thanks for the suggestions. This is a great group and I know with your help I can get my car going.

Chip

 

[TType84]

38psi is high for vacuum on.. thats like, 50psi base fuel pressure or more.

swapped ecms... chip?
if this is still an 84/85 ECM, you *MUST* have a chip made specifically for an 84/85 ECM & MAF, the coil paks and the modules are also *NOT* the same. If you have some goofy combination of 84/85 and 86/87 parts this could be a huge reason why things arent working how they should ..

 

[crazygn]

I have a caspers tool to set cam sensors a great tool . You just set the crank pully and plug it in to the cam sensor and turn it and the light will come on when it's set. What year is the ecm 84-85 or 86-87 i had a problem like this when i changed to a 87 ecm , i had to change the little chip in the ecm to so i could run the 85 coil and module. just a guess.


These guys will get yea running in no time.

 

[T- Type Tim]

I would look at the converter before the cam sensor, when my cam sensor was out of adjustment it backfired louder than it had ever before. As for the converter, I put a hughes 2500 in and that piece of junk slowed my car down considerablely. (would'nt even spin the stock tires at the time), I since put the thing in the trash where it belongs.

 

[chip]

Thanks for the suggestions.

I'm reasonable sure that the cam sensor is set right. Also, I've adjusted the FP a lot and it doesn't seem to significantly improve the car. I think it has a different problem.

The chip is definitely for an 85 with 36# injectors. I also tried a different 85 chip (a hypertech) and that didn't do much for it. My ECM is stock so should be correct for the 85 chip.

I have done no work with the transmission or torque converter. It makes sense that might be the problem. Is there any way to verify that the converter in there is the correct one? Is there any way to test that it is working right? The transmission doesn't seem to want to upshift on WOT (I have to lay off it to get it to upshift) and I'm sure the TV cable is correct. It shifts fine when not WOT. Do you think a shift kit will help this problem (assuming the tranny and torque converter are right)?

Chip

 

[TType84]

If you do have a 3" UP pipe too... that could be one reason why you have no bottom end and 10psi boost.. 3" is pretty HUGE for an up pipe..

 

[turbowrenchhead]

One way to see what your convertor stalls to is to do a brake stand. Put the car into drive and little push on the brake start pushing down on the throttle and see at what rpm the car wants to break the tires loose. That will give you a general idea.

 

[chip]

Well guys, I fixed part of the problem. I installed a new wastegate solonoid and replaced the EGR and PCV valves. Although that didn't seem to help a great deal, I noticed that there was a vacuum line going from the wastegate to the vacuum block that was shown as capped in the wiring diagram I have. So I took off that vacuum line and capped both ends, the boost went from 11 psi to 16 psi. Although its now running a little faster, I still haven't found the root of the problem. Besides, I have the wastegate adjusted way out and with the TE-33 turbo I should be getting more boost than that.

It still seems like its not running like it should. I have a stock 1984 Corvette (205 HP) and even with 13 psi boost and no performance parts, the T-type should blow the doors off the vette. But I have 16 psi boost and a ton of performance parts, and the wins by a fairly large margin off the line.

By the way, I have a guy who is a GN expert helping me out. He has built up 5 or 6 GNs and his runs low 11s so I have faith that he knows what he is doing. He is baffled by the problem, and so am I.

Thanks for the help you all have given me. Hopefully with your ideas I can get this thing going. Sorry for the long post...

Chip