wjiroc86

OK I looked didnt find anything helpful in here.

I have a 89 tbi Camaro I modded it out and now it idles at like 3000 on a cold start, the timing is right on tdc ive tried advancing and retarding it nothing has helped, and its got a brand new distributer what could make it do this im stumped and i really miss my car. Any imput thats not rude is highly appreciated.

acadburn

just curious what mods did you do to it... any chip work perhaps???

also id assume ud mention this but did u mention it but did it start idling hi after any specific mod....

dose the idling return to normal after it warms up?

89IROCTBI

Clean your IAC lately?

Darkshot

iTrader: (4)

You sure your tach is working properly? Very common.....

wjiroc86

Sorry it took me so long to get back to this, but i ported the top out like on the tbi tutorial and raised the injectors up, it started running high after that, i made shure that the throttle wasnt hung up anywhere or if the butterfly valves were open and it was all good, ive had the car running to warm up and no change, but also when i touch the throttle hard it backfires through the tbi... guys im really stumped on this one.

Also the tach seems to be working right because i have a flowmaster and its easy to hear the super high rev on it.

rough

all vacuum hoses hooked up?

wjiroc86

yep or blocked off, it doesnt seem like the injectors are firing right, sprayin to much and not pulsing seems like driping more than anything else. ive been workin on this for a week its driving me insane....

rough

Did you rebuild the TBI unit? or just grind down the top and slap it back together ?
----------
Or how about the Ignition control module under the distrib? check that out also.

89IROCZ28

iTrader: (14)

I had similar problems, but not right after making the TBI mods. Here are some things to check. To some I may sound like a broken record, but this is what I checked and/or found potential problems while solving the problem I had. I'll start w/ what ended up fixing my particular problem, the rest are in no particular order.

- Coolant Temperature Sensor (CTS). Resistance should be around 3K ohms cold and close to 200 ohms around 200 deg F. It's probably OK if it's close to this. A bad one makes the ECM think it's cold and calls for more fuel. Costs about $15-20 to replace.
- Idle Air Control (IAC) valve. Check out the IAC adjustment procedure found in the Tech Articles to make sure the IAC is extended (closed) all the way. With the air filter housing removed, block the passage leading to the IAC. If the idle drops, the IAC isn't closing all the way, something is holding the IAC open, or the throttle is passing too much air.
- Exhaust Gas Recirculation (EGR) valve - Check to see if it's stuck open.
- TBI to manifold gasket leaks.
- I also went through plugging all vacuum ports on the TBI & manifold to determine if any tubing or components (PCV, MAP sensor, etc.) were leaking.

You may be fighting multiple problems. High idle is usually a vacuum leak of some sort. Excess fuel is either the ECM calling for more fuel or the TBI injector o-rings, or the injectors themselves are leaking. A backfire often ends up being ignition related (cap & rotor).

Hope this helps.

Ronny

iTrader: (1)

Sounds like injectors are not functioning correctly. Rebuild time. I would send to Ficht(spell?) and they will clean and rebuild.

Also probable vac leak. Possible IAC is stuck. Visually inspect IAC and watch movement key on - engine off. You can jump ALDL and do same. Do not cycle IAC removed and outside of TBI unit.

wjiroc86

i went and bought a new iac and it didnt do anything different, i bought a new coolant temp sensor today and it didnt help any either, the injectors are spraying like crazy and its getting gas all over the intake, my timing is firing at tdc.

Ive given up and now its going to the specialists out at our local garage... dont be mad at me i just dont know how to fix it lol

89IROCZ28

iTrader: (14)

Sounds like either the injector o-rings or injector pod gaskets are leaking. I can't imagine fuel getting on the manifold if the fuel is coming from the injectors themselves. Can you tell if all the fuel you're seeing on the manifold is coming from the injector tips or somewhere else? There are two o-rings for each injector, one near the tip and another near the top that backed up w/ a thin washer. These two o-rings make sure fuel only comes through the injectors ... unless they are leaking. The ones near at the injector tips can be a little challenging, but a little light weight oil helps to get them seated properly w/o damaging them.

Then there's two gaskets for the injector pod that could squirt fuel everywhere if they're leaking.

A complete TBI rebuild kit is around $25-35. It'll include all the gaskets, o-rings, etc.

wjiroc86

if the injectors werent right it would leak when i turn the key right? im pretty sure the only fuel coming out is from the injectors, it just seems like too much fuel, i bought the rebuild kit its like 45 bucks here and i lubed the o rings too... hopefully the shop will have some good news for me and i can drive it home soon im just happy to be getting it fixed...

and thanks to everyone for ya'lls advise...

rough

no, only when running will it leak, when you turn the key your just priming the pump.


Those O rings are a pain, took me a few sets before i finally got it to sit right and not leak.
----------
If you can make a vid or take some pics of its running and the spray pattern that would help. If it leaks after you turn off the car, its a Seal somewhere probably the O rings.

racerquinny

iTrader: (1)

my car does the same thing. it idles at 2000rpm when warm in park. but fine when in drive. my problem i think is that my butterflies in the tbi, it is sticking cause of a peice of the butterfly is chipped. letting air into the motor, more then usuall when in motion. also i was told that the IAC motor could be bad



thats just my problem right now, i have to get a new TB. unless my mechanic at work can check it.

wjiroc86

Im going to see what they are saying tomorrow, hopefully they can fix it cheap if not... well im not gonna lie... im not paying =] i love my parents lol, i was thinking about just going to the junkyard and finding another one, last time i was there the guy had like 5 of the right ones and said he would take like 30 for any of them or 60 for 3 i was like wow... He seemed kinda cracked out or something..

BluFBdy

iTrader: (1)

so youd have a 1 in 3 shot at a lucky TBI not experiencing the same issues. Id go pick one up personally and put it on your car and see if your mod screwed it over.

If not im stumped thats the only thing i can think of from what youve listed that throws a red flag

dwillis

iTrader: (6)

check egr valve.vacuum leaks around the tbi unit.disconnect the throttle cable from tbi and start it.also you may just simply need to idle it down,but I think the throtle cable may be holding it open a bit,or the IAC is jacked.

wjiroc86

Well the wrong gaskets from the geniuses at my autozone gave me the wrong tbi rebuild kit... i feal a little dumb lol... but i need to ask for some more help the car has a great idle now, but its 10 degrees advanced.... and thats where it wants to be, if you know what i mean, why would this be that way? also it bogs in high rpms (thinking maybe because it will backfire at tdc)??? I know i might sound like an idiot maybe but i only know carbs, Does everyone have alot of problems with their tbi's?

Thanks In Advance guys

BluFBdy

iTrader: (1)

by "wants to be" do you mean the motor wont idle proper at the 0*? or that you set it to 0* and then it readjusts itself? If its the bad running im stumped but if it keeps adjusting itself you have to be sure to disconnect the brown/tan wire up by the strut on the passenger side before adjusting the timing or the ECM will just put it right back

wjiroc86

i have done that i am getting a new fuel pump tomorrow, and i have it set with the dist to tdc, but it wont run right there i have to adance it like 10 degrees or so before it will run at any high rpms...

Im kinda confused about a fuel pump should i run the one for a stock 305 tbi or a 5.7 mpfi? the 5.7 would flow more right? will my tbi regulator hadle it? and i looked at autozone.com and a 5.7 one is like 2 dollers cheaper there, and my dad who is a mech said something about getting one for the bigger motor???