bulletboy29

The TPS on my CC Q-jet is very loose. It causes the readings on my voltmeter to jump around when I shake it and causes the computer to throw TPS codes. It was loose when I bought the carb new a few months ago, but hasn't caused problems until now. It was reading over 3 volts at idle, so I tried to adjust it and could only get it down to 1.4 volts. Is there a way to tighten it up or do I need a new one?

bulletboy29

ttt

naf

iTrader: (7)

To find out if it's bad (or improperly installed) pull it out and check it for a linear voltage reading as the plunger is pushed in and released. Sounds like it's bad though.

bulletboy29

Is there some kind of easy fix where I don't have to take the carb apart? Like a piece of wire, duct tape, and a match. I love this car!

Vader

The easiest fix is usually the correct one. The "quick-and-dirty" fixes usually create more work and frustration later, so taking short cuts seldom is a short cut. Just install the spring below the TPS and have it solved permanently:

bulletboy29

Thanks for the diagram! From doing searches, it's looks like I will need a new TPS, carb rebuild kit, and a flashlight to help find parts that fall out when I take the carb apart. This TPS lasted for about 3 months, is there a better TPS out there?

Damon

Yeah, GM (Delco) units are still available from the dealership. Expect to pay TRIPLE the cost of a parts store cheapie ($60 vs. $20). It is a higher quality unit than the aftermarket knock-offs, however.

Remember that the part you plug your TPS plug onto is just the connector- the TPS itself is deeper inside the carb and has wires running to the TPS connector on the front of the carb. It's important you don't pinch these wires when you put the airhorn back on the top of the carb. It's also VERY important to get the little metal dowel that sits in the airhorn and pushes on the TPS plunger from above situated correctly when you put the airhorn on. Some of them can be real SOBs and I've taken to removing the accelerator pump arm and dropping the dowel in from above AFTER putting the airhorn back on. But removing the accelerator pump arm is almost as difficult!

Getting the TPS stuff all lined up and dropped in correctly is one of the most difficult parts of working on a cc-QJet.

bulletboy29

Sounds like fun! Is there a good chance that I will screw the whole carb up or is it mostly just a PITA? I've never taken a carb apart before, so I'm really dreading it. Tell me the worst thing that could go wrong, so it won't be a surprise if it happens!

Damon

Oh, boy. You sure picked a tough one to start with. There's plenty that can go wrong, usually involving the TPS, the choke or the mixture control solenoid and it's settings. Not to mention the joy of losing small parts! I would get with somebody who knows cc-QJets to take you through it the first time. I do them in my sleep, but I've done literally hundreds of them.

If you lived anwhere near Philly I'd help you out, but you don't.

Go slow, PAY ATTENTION while you take it apart (a few digital photos during disassembly wouldn't hurt!), follow directions during reassambly and cross your fingers.

bulletboy29

I'm going to try to find the receipt for the carb. Surely Autozone gives some kind of warranty on this thing! If it's not under warranty, then I might need your guidance when I do surgery on it.

bulletboy29

It was still under warranty!!! Autozone traded them out today, so I'm good for another few months.

Jetmeck

iTrader: (3)

Been through three TPS in about 50k miles, two aftermarket and just today my AC/DELCO $56.00 TPS decided to go south, you are not alone !!!!!!!!!!!1

naf

iTrader: (7)

At least you guys are checking and replacing them. There's a ton of LG4's running around with bad TPS's whose drivers think it's normal to get 16-18 mpg, crappy part throttle performance and a lingering gas smell. Even at $56 you'll pay for it with your mileage increase in no time.

After you change one a few times it does go quicker.