Need help solving mystery problem

[paintballrocker]

Hey all the past weekend I hit a mud hole that was a little too deep. The engine shut off it's self so I got the truck pulled out and took the intake off to find water in it. After I got it dried out it fired right up. It ran weird on the way home like dropping down in Rpms when under load. Now two days later when I start it it idles really high around 1600 rpm and when I'm driving it revs up alot higher before shifting gears.

I'm worried if this is a bad thing or not. I'm thinking most likely I flooded a sensor or something that's causing it to run odd like this.

Any advice on what to do?

[F9K9]

For a moment I was thinking that you may have hydrolocked (sp?) your motor when you found water in the intake. Any MIL or SES lights?

[paintballrocker]

Yea I thought the same thing bout hydrolocking but I didn't thankfully. I did have a check engine light after it happened but it went away after A day of driving. But now i haven't had the above problem since yesterday. Now it's idling fine but still takes a little longer to shift tho

[F9K9]

Have it scanned for the codes. It should still be stored in the system. You might have gotten something wet. Happened in my heep. I only had 2nd gear in the auto (limp mode) and I had lights on the switches for rear wiper, defrost and the locker compressors ran with the key out of the ignition. Luckily things dried out and all went back to normal.

[riceburnr2005]

I agree water can do some weird things. I had my crew up over the hood in water once, lights started going off on the dash, but after a couple days it was back to normal.

[paintballrocker]

well its been a few days, i had the SES light come one for about 3 days and it just went away by itself. But im still having weird problems. First my truck norm idles at around 1100 and then goes down to around 600 rpms. now after this incident it idles around 1700 and goes down to 1100. also its shifting weird, it keeps wanting to rev higher before it shifts and it constantly wants to jump from gear to gear like its searching. and lastly if im going under 15 mph in first gear and i let off the gas pedal, the truck will accelerate by itself and rev up and shift into 2nd.

The ways its acting has me worried. im gonna disco the battery and see if letting the computer reset solves anything, if not im gonna hook it up to a code scanner.

[green02crew]

Scan it first and check that.

[paintballrocker]

im going to tomorrow before work. but it scared me today. i drove it and put it in park before i turned it off and the rmps keep rising to above 2000 so i shut it off before it rose too high

[HenryJ]

Check the IAC and TPS

[paintballrocker]

Thanks HJ. ive been researching this problem, im hoping that cleaning the throttle boddy, IAC, MAF, and TPS might resolve these issues. ill see what codes pop up when i scan it tomorrow

[HenryJ]

Check the TPS sensitivity thread. Use a multimeter set to ohms to read a nice smooth throttle movement. Skips or drops indicate a bad spot in the TPS potentiometer.
The IAC is harder to diagnose. Look for a clean ring on the pintle seat. It needs to close and seal properly. They are fairly cheap to replace. Under $25. It might be a good idea to see if one is available. Most auto parts stores carry them.

[paintballrocker]

thanks for the idea on shooting the wiring on the TPS. Ive heard that to check the IAC is to remove it but leave it plugged in and see if it actuated once the engine starts. Ill try to clean everything and troubleshoot before i order parts being as im overseas

[paintballrocker]

well i got a chance to scan it today at work. got 6 diff codes. MAF, TPS, n MAP sensors, plus bank 1 & 2 rich codes. so im gonna shoot some wires and clean eberything this saturday and see if anything needs replaced. Do you think those items would cause my tranny to be shifting weird?

[HenryJ]

TPS could.

[F9K9]

TPS could.

+!

[paintballrocker]

great to hear! i was worried my tranny was going on me

[paintballrocker]

forgot about this thread for a few weeks. i got the MAP sensor and TPS replaced, its not throwing a code any more. so thats solved, but it still isnt idling right. so im gonna replace the idle air control valve and see if that helps. if not, is there a srew to manually adjust the throttle blade to adjust idle?

[HenryJ]

The throttle blade can not be adjusted. That would skew the TPS reading.

Check for a stuck EGR valve and clean the throttle body good, if you have not already.

[paintballrocker]

already cleaned the throttle body. ill have to check the egr. ona side not though, i noticed with the cable for the cruise control into the throttle blade (next to where the throttle cable mounts) it holds my throttle blade open. could i just back off the threaded fitting for the cruise control to close my throttle blade? would that help with the idle?

[HenryJ]

Perhaps. I don't think there should be tension against either cable. That said I can not run out and confirm that either.
When you look down the throttle body is there a gap around the butterfly like it is being held open, or is it pretty much closed and tight at the edges?

Checking the resistance at the TPS should indicate if it is being held open above the TPS closed position. Check out the Throttle Position Sensitivity thread for the TPS operating range.

[hootz]

What kind of idle trouble are you having? Too slow, too fast, dies at idle, rough idle?

[paintballrocker]

Perhaps. I don't think there should be tension against either cable. That said I can not run out and confirm that either.
When you look down the throttle body is there a gap around the butterfly like it is being held open, or is it pretty much closed and tight at the edges?

Checking the resistance at the TPS should indicate if it is being held open above the TPS closed position. Check out the Throttle Position Sensitivity thread for the TPS operating range.

yes with everything attached on the throttle body, there in tension on the cruise control cable and that holds the throttle blade slightly open to wheres theres roughly a 1/8" gap between the wall of the throttle body and the blade

What kind of idle trouble are you having? Too slow, too fast, dies at idle, rough idle?

after replacing the bad sensors its idles really high, between 1500 and 2500 rpm. normally it would idle at 1200 on start up and drop to around 700

[HenryJ]

What has changed? Something changed to hold the throttle blade open. What was it?

[killian96ss]

Try disconnecting the cruise control cable and see if the throttle blade closes any further. There definitely should not be a 1/8" gap when the throttle blade is closed. A gap that wide will cause the IAC valve to completely close off the idle air passage which prevents the PCM from lowering the idle any further. Maybe something in the cruise control unit failed which caused the throttle to be held open a little bit?

Steve

[paintballrocker]

Try disconnecting the cruise control cable and see if the throttle blade closes any further. There definitely should not be a 1/8" gap when the throttle blade is closed. A gap that wide will cause the IAC valve to completely close off the idle air passage which prevents the PCM from lowering the idle any further. Maybe something in the cruise control unit failed which caused the throttle to be held open a little bit?

Steve

im not sure what changed to adjust that cable tension. I ordered a new IAC valve, cause that was the only sensor left that i didnt replace that controls idle. so if replacing that doesn't change anything im gonna try disco'ing the cruise control cable and see if that helps. Im sure one of the two will fix my problem

[HenryJ]

The IAC valve can only compensate so much. If the blade is being held open then then IAC closing fully may not be enough to compensate.
Do check the TPS readings. I'd probably adjust the cruise control to zero the TPS , or seat the throttle on the stop.

[paintballrocker]

well i backed off the cruise control cable till it had slack in the line. truck is idling low now thankfully. but it still isnt idling like it use to. so im gonna put in the new IAC vavle when i get it and try to mess witht the cruise control cable till it idles like it normally does