Creeping Idle After New Tps Install

[snakedoc67]

Just installed a new TPS and have it adjusted correctly ( 4.86X  ,17= .82). I used a TPS for an automatic instead of the manual one, and I adjusted per manual TPS instructions. Should I be using the four wire connection and use the automatic instructions?  I am getting a high RPM that creeps up as the engine runs. The first two test starts it climbed up to 4000 and stayed there, now it is around 2500 but creeps up right away.  How much would the vaccum lines around it have an effecct fi they are not hooked up correctly? 

 

Other things I have played with in the last couple of days have been to clean the contacts on the coll, replaced the TPS, pulled the fuel sending unit out to put new hoses on it. 

 

Looking for any suggestions, temp is supposed to go from the high 40s today to the mid 20's and lower the rest of the week and I don't have anyplace inside to work on it. lol 

[cruiser54]

Vacuum leaks could affect it as could a dirty throttle body and IAC.

 

Have you ever cleaned the TB and IAC?

 

Did you do the sensor ground test before adjusting the TPS?

[snakedoc67]

I had the entire TB disassembled and cleaned it two days ago. I did the sensor ground test and had no variances when i was shaking the wire harness. I put an JY fresh vaccuum harness and it took care of most of the issue. 

 

I put the old TPS back in just to see what would happen prior to going and getting the vaccum harness. Currently with the old TPS in and adjusted, It idles a lil high still. I have not reinstalled the manifold air tube either, will do that as soon as I put the net TBS back in and see what happens. The PO had installed a K&N Filer at the end of the air tube from the manifold and took the airbox itself. 

[cruiser54]

Never had this before?

[ComancheKid45]

Check your intake manifold bolts. Even 1 slightly loose can cause some weird idle symptoms ;)

[snakedoc67]

After reinstalling the new TPS, I got the same result as the first time, idle  between 4000 and 5000.  I put the old one back one and reinstalled the air tube and filter since that was causing it to surge a lil bit. Idle is now around 2-3000. Is it possible i got a bad TPS from the store? 

[cruiser54]

After reinstalling the new TPS, I got the same result as the first time, idle  between 4000 and 5000.  I put the old one back one and reinstalled the air tube and filter since that was causing it to surge a lil bit. Idle is now around 2-3000. Is it possible i got a bad TPS from the store? 

Yes. 4000 seems awfully high for a TPS issue though. 

 

You "disassembled" the throttle body?

 

Maybe this will help. Perhaps something didn't go back together properly.

 

Use this for verification purposes.

 

Cruiser’s Renix Throttle Body Butterfly Adjustment

Okay. Let's start from scratch. First off, that's not an idle adjustment screw. It's a throttle butterfly stop screw. It's purpose is to allow the butterfly to be as close to completely closed as it can be without binding or wearing into the throttle body. It was never intended to be adjusted in the field. But, Uncle Bob didn’t know that, did he?

Engine off.  Back off the butterfly stop screw with a 3/32” allen wrench until the butterfly is completely closed. Now. turn the screw in until the FAINTEST movement of the butterfly opening is detected. This can be done more easily with the throttle body removed. If you remove the throttle body, be sure to replace the gasket underneath it after thoroughly cleaning the old one off.

  Revised 07/07/2012

 

[Akula69]

Despite all the good responses, I'd suggest checking for vacuum and/or TB/manifold leaks the simple way:

 

Start truck

Spray TB or Carb cleaner at the various areas in question. Take care to check the manifold gasket first before it gets too hot.

 

When the idle changes abruptly you've found the problem.

 

If you are worried about the high RPMS while doing the test, unplug the MAP sensor. This will artificially lower the idle, (but will obviously will produce  a false reading if you spray the cleaner there).

 

Let us know what you find.

[mjeff87]

Check your intake manifold bolts. Even 1 slightly loose can cause some weird idle symptoms ;)

 

 

X2 on this ^^^^

 

Jeff

[cz777]

i had a broken wire in the harness going to the tps ...talk about drive you nuts -them old wires with all the flexing they do - use a vom with conductive   alarm  and follow the wire /wiggle test 

[snakedoc67]

THanks for the advice, will be getting a different TPS to test the possibility that my new one was bad. Will have to wait til its a lil warmer before resuming this but at least its driveable at the moment for stay in town trips. lol 

[92tanMJ]

Not to thread jack...but do all years need the TPS adjusted for just the renix motors?

[HOrnbrod]

Not to thread jack...but do all years need the TPS adjusted for just the renix motors?

 

Just the Renix. When you replace the TPS on an HO, it usually runs up to about 3K RPM or more on first start, then slowly comes down as the ECU massages the reference voltage. IF everything is working right.

[92tanMJ]

 

Not to thread jack...but do all years need the TPS adjusted or just the renix motors?

 

Just the Renix. When you replace the TPS on an HO, it usually runs up to about 3K RPM or more on first start, then slowly comes down as the ECU massages the reference voltage. IF everything is working right.

 

That's what I thought, thanks Don :cheers: