NEED HELP! Codes:P0171, P0174, P0304, Symptoms inside

[etlsport]

my TPS always shows up on the scangauge.. ill get some normal readings tomorrow for different situations

[Jolly Roger VX'er]

my TPS always shows up on the scangauge

I'm thinking that if his idle was just out of range (i.e. 50+rpm) it would be the IAC that was bad...but, if it is WAY out of range (alot more than 50+) & not caused by a vacuum leak...and the Throttle Position Sensor isn't showing on the scangauge...I'd be steering in that direction------>(TPS).


I had a car in the past that would kick the code of "idle higher than expected" but was only idling in excess of 50 rpm over the normal idle...it was the IAC that was bad in that case.

[taylorRichie]

It's still idling between 2500 - 3000. I can't find a vacuum leak anywhere, and I used the start fluid method. And carefully examined all of my hoses and fittings...

Is there a way to use a boost/vacuum gauge to determine if there's a leak? ie, the vacuum PSI at a given RPM?

My Scangauge doesn't return anything when I switch to TPS, it only shows

__TPS with nothing to the left of it.

[WormGod]

Mine idles in the same range from a fresh startup. It is even sneaky at times and decides to randomly do it while driving, but only when I let off the gas to come to a stop. Causes me to have to leave a longer distance between me and the car in front of me, heh. It will buck forward as I step on the brake. Very rare but I don't need to hit someone in front of me.

I have been playing around with ideas for a few months now and STILL have yet to do anything about it. I only just got a new battery this weekend to get it back on the road after a couple months, so I will be back on the case now. I have only thrown 171 and 174 previously. The funny thing is, if I clear the codes without fixing them, it will run fine for about a week. Then, the issue comes back and the codes appear again. I have concluded that a new MAF, FPR, and EGR should be on my list of things to do. I cleaned the MAF several times, but the screen isn't exactly pristine anymore. And I never did replace the FPR after the my S/C install, so that won't hurt. My EGR has been cleaned to the bone and there is no getting it any cleaner, and it is a slight disaster. Definitely won't hurt. I do not think I am gonna touch the O2 sensors unless it is last resort time. There is already a laundry list of money to be spent.

[nfpgasmask]

__TPS with nothing to the left of it.

I am pretty sure the VX does not show this. I will check my scan guage on lunch to verify.

Good luck getting her fixed up.

Bart

[Jolly Roger VX'er]

Just found some relevant threads in case you didn't already see them:

http://www.vehicross.info/forums/sho...&highlight=maf

http://www.vehicross.info/forums/sho...ight=high+idle

http://www.vehicross.info/forums/sho...&highlight=maf

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

http://www.vehicross.info/forums/sho...highlight=idle

[taylorRichie]

Thankya thankya thankya...

Looks like the IAC is going to be the culprit... as corroborated by the man links you sent...

Most people on here have referred to it as the Idle Control Valve, or ICV which is probably why my searches for IAC didn't come up. But your searches for IDLE showed a lot...

I'm going to go disconnect my battery for 30 minutes to get a fresh restart (apparently needed after messing with the IAC) and then if the issue persists (expected) then I'll pick up an IAC, Part#8-17112-648-0 (for anyone's future reference)

[nfpgasmask]

Richie, I was wrong, my scanguage does indeed show a reading for the TPS!!!!

Bart