Hi guys I have a question that maybe someone can answer. First off I will give the story on the car. I just acquired a 92 z28 5.0 with a factory purple haze paint job. The less than smart gentleman had issues with the car and just started hacking away and random things. I bought it for $1000 and now I am rebuilding it to its original glory. After replacing the thermostat, flushing the block and radiator, cleaning the throttle body and intake I noticed the TPS was loose. The car will turn over but not start. I took a reading on the TPS and after proper adjustment I'm getting .46 on idle but WOT is only pushing around 3-3.2. Should I just replace the TPS or is this about normal? Also I took a reading of my injectors and all are reading at 17 ohms but the manual says they should read 11-14 ohms. Can anyone with more experience with these f body cars help?

 

The tps isn't adjustable on speed density TPI or TBI that year. The computer takes what voltage it gets to start and works with that IIRC. The resistance is a touch high but if they're all that way I wouldn't conclude that as a major problem.


Start at the basics. Check fuel pressure. Check spark.

 

It doesn't seem like I'm getting any fuel pressure to the manifold. I thought that I would check the fuel filter to see if it was clogged and to my surprise the previous owner cut it out and replaced it with tubing. The tubing is currently pinched in half so I'm pretty sure that's where my pressure problem is coming from

 

These are the lines

 

Yeah, that bend is no good. Can you hear the fuel pump prime?

 

Yeah the pump is priming but if you switch the key to off and wait a min or two and turn it on again it will prime again. I think what is happening is the pump can't fully prime the line due to the restriction and I'm not getting enough pressure to my injectors

 

You can do the fuel pump prime over and over after the ECM time out. this is normal. If your unsure of the fuel pressure use a fuel pressure gauge to test it stop all the guess work.
Your tps grey wire is a 5v ref. the 90-92 tpi tps is non adjustable KOEO .76vdc on the blue feedback wire. A 85-89 tps is cheaper and will work on your tb but will need to be set. Wot will be 4.50-5vdc .

 

On the feedback wire I'm definently only getting .46 but the manual says that's within range. A mechanic told me I should get almost 5 WOT and its nowhere near that.I'm going to hook up a pressure gauge and see what I'm getting on prime and while cranking

 

http://www.iroczone.com/2009/10/adjusting-your-throttle-position-sensor-tps/
http://m.ebay.com/itm/261649642698?nav=SEARCH
If the grey wire is sending 5v to the tps KOEO the potentiometer resistance is to high.

 

Just wanted to let everyone know I got her running today. I had to cut the pinched fuel feeder line and replace it but it is sounding good. Its not wanting to start by itself still but if I give it some gas it will fire up and hold a steady idle. Not sure if its junk in the injectors or the TPS or just a carbon buildup

 

Hey guys just an update. Went out to crank up the car and its flooding bad! Have done some investigating and after checking my tps again along with my MAP, injectors again, replaced all of my dry rot vacuum lines, and checked my ECU for any blown resistors I have come to the conclusion it has to be my coolant temp sensor. I have tried to ohm it out and I am not getting any kind of a reading on it. Now I know that if it is bad then it will send the engine into flood mode so I'm really hoping this is it. I also need to flush the oil and change the filter now because there is gas in the oil. I talked to a buddy of mine who is a mechanic and he says that if an engine constantly floods then it can push gas down into the crankcase. Hopefully this is the end of the road

 

Glad it runs. It does sound like you have a CTS problem. Most cases that I've had gas leaking past rings to the oil, all I had to do was change the oil extra frequent till the oil was normal. It's not good for it but I don't think it'll kill anything at this point.

 

Update. Almost pulled my hair out trying to figure out why it wasn't running again. Got out today with determination and found out I had a bad distributor cap and rotor. The point on the cap that goes to the coil was wobbling around and the rotor had carbon and buildup on it. Changed both and boom it fired right up. I am beside myself with happiness. I'm not a mechanic and the pride I feel for troubleshooting my own engine problems gives me a sense of accomplishment like no other.

 

Congrats.