87WS6

iTrader: (1)

Alright. I had my car in the shop recently to have my lifters replaced and my idle issue resolved. They got new lifters and took care of this odd rattle comming from where the coil mounts. I drove the car twice and then the idle issue came back. Not as bad but it came back. So I took it back to the shop and told them to track it down and take care of it. They asked me to buy a IAC valve. So I did. I dropped it off over there.

I go up there when the car is supposed to be ready. It isn't ready. They are messing with my MAF sensor. They have my air box all pulled apart and are screwing around with it. They said they took the MAF off of a 5.7L TA and it's doing the same thing mine is. They didn't even install the IAC valve. They are telling me now to replace the MAF. I asked them why theirs didn't work. They say it is because a 350 and a 305 MAF are different. Yet they tried it anyway. They first suspected my ECU but after reading so many horror stories on this site about shops saying that only for it to not be the problem. I told them to triple and double check that because I didn't believe them. I also checked to see if it was the ignition system. I have replaced the coil because mine was making a wierd electronic whine.

My question to you guys is this. Is the MAF for a 305TPI and a 350TPI car the same? Could this be the root of my idle issues? They haven't checked my O2 sensor as far as I can tell. They already cleaned the old IAC vavle and throttle body. So what do I do? I need some advice soon. I have to decide what to do with it by about 5 today.

IROCZ88x

hm, sounds either stupid or maybe its just a hard problem to diagnose...i dont see how the maf would be causing such a problem, im not sure but i also dont see why a l98 and lb9 maf would be different seeing how all they do is measure incomming air...clean and square away the iac and tps and clean out throttle body like i guess u have...what kind of idle issues are u having?

SMURFN' Z28

iTrader: (2)

and that is why i never take my car to a mechanic. they will just start guessing on whats wrong and replacing stuff, then you get stuck w/ the bill. between me, my friends and this board, i manage to figure out most things on my own.

Fevre

Maybe give more info on your set up. Could possibly be bad/dirty inj's or too large of inj for your current ecu set up. Any mods to your eng?

87WS6

iTrader: (1)

Well my RPM's flutter when the car is at idle. They will fluctuate by as much as 500+ Rpms. On rare occasion the car will stall on me.

My car is a pretty much stock LB9 A4. I have cleaned the TB, replaced and reset the TPS sensor, cleaned the IAC valve. I have a new Accel coil. (Installed to correct a different problem). I have a 3' catback exhaust. So my car is pretty stock. I have reset the computer before. I have all new lifters in the engine. Freshly changed oil. I have worked with the information on this board on several occasions to fix my idle issue and I never got anywhere with it. That is why I finally took it to the shop.

I am not getting any SES lights at all during this either. They say they are getting weird codes from the ECU. Yesterday they said it wasn't my ECU. They seem sure of that now. I told them to reset it and make a new prom if they had to. They have the equipment for it. And as always the advise is appreciated. I am in over my head currently on this matter. My injectors are stock and I have run about 4 cans of injector cleaner through the system over the last few tanks of gas. The car doesn't seem to be starving for fuel. Other than the exhaust and the coil my setup is totally stock as far as I know.

dacuma

well look don't let them replace your maf, that's a $200 dollar guess. Trust me I 've been through something like this, and I'll never take my car back to a mechanic Usually when your maf goes bad your going to get a SES light. And just because they have said they have clean your IAC doesn't mean they cleaned it good. If I were you I would get your car back, and try to fix it yourself or take it to someone else. As Smurfn'Z28 said it's a guessing game for them, and in the end your stuck with the bill. At least double check your IAC make sure they cleaned it right.

bnoon

That's right... Them guessing at it costs you more than just guessing yourself.

Also, injector cleaner running through the tank is only good if you do it every 2-3 oil changes, not once in a blue moon because the car is runing crappy. If you do it once in a while, all you do is break loose bigger chuncks that can actually cause a bigger blockage than what you're trying to remove.

When injectors get dirty/worn, they tend to stick open, not closed. That would give you to much fuel, not starve it as you stated 87WS6. I'd pull the injectors out, check their resistance (16 Ohm IIRC), and back flush them with a fuel injection safe carb/TB cleaner.

383 rocket bird

I would replaceyour O2 sensor being that it is a long overlooked tune up item on most cars.

REDZ28

Wow there must be alot of Mechanics in here with all these guess's Im an ASE master Tech so mY guess is as good as all yours..... I Guess

Jekyll & Hyde

Change a couple of the sensors out first. I would change the 02, IAC, and TPS. Spend a little cash to get those out of the picture. Sometime you just have to. Did you set the idle screw?

Tmony69

I'm running a MAF from a 350 on my 305 now, and have no trouble at all. I did cut out the screens, and fins inside.

87WS6

iTrader: (1)

Well now they replaced the MAF with one they purchased and they said that seems to have cleared up the problem. They are doing some work on my TB now. I told them to just replace the IAC valve since it was pretty cheap.

Now though I am getting detonation with my accel coil in there. Any ideas on that one? Is there something I need to do besides just replaceing the coil? Do I have to use another prom?

dd85T/A

The MAF is the same. After messing with your IAC and TPS you need to reset everything. If you have a scanner check your IAC counts. If your idle was good before and you didn't change anything then it should be something easy. I bet you just need to adjust your Min. Air. Good luck.

Morley

305 and 350 MAF is the same unit. The coil won't cause detonation.
Get your car out of there and either learn how to fix it yourself or take it to a REAL mechanic with experiance with TPI's.

87WS6

iTrader: (1)

Well I would love to be able to fix it all myself. However I am not that far along yet. Also my idle was screwed up almost the whole time I have owned the car. I have been through everything on this board to try and fix it. I have fallowed all the advice and the problem is still there. Anyway I have reset everything after replacing the TPS sensor and all the other stuff. Results were always the same. I tried and tried to get it fixed on my own so many times. I finally said the hell with it. Took it to a mechanic. He had done some work for me in the past. They seemed ok. But I think they are in over their heads now.

Morley

Well, if you did all of the things people have suggested and followed the tech articles on adjusting idle and tps and it still didn't fix the problem, then don't expect your "average" mechanic to be able to come up with a solution.
On a board like this you have the clumulitive knowledge of hundreds of people with vast amounts of experiance. Between all of the people here I would say that we have seen about every problem that can arise with a TPI system.

I would fork over the $44 for the updated factory prom and see what that does for your problem, even if it doesn't fix it you'll still be cheaper than changing MAF's and other more expensive sensors not to mention that you'll have a spare prom for future use and troubleshooting.

87WS6

iTrader: (1)

Well I was at the shop yesterday and they seem to have taken care of almost everything. My new TPS sensor was bad out of the box. I saw the results of it's adjustment up and down the range on the diag computer myself. We installed a new one and that took care of the problem. They are going to make me a new prom, and it seems that some of the minor fluctuations that my tach is picking up are because my tach is screwed up. It would seem like that is the case. The diag equipment shows the rpms steady and without fluctuation. It is still idling high. Which they are going to take care of. It just seems that I had one of those hard to diag problems. It's almost all taken care of now. I should be getting the car back.

I had the opportunity to watch them work on it yesterday. And I got to verify all their results on the diag equipment myself. So I feel alot better now. I really would like to learn to fix all of this stuff myself so that I don't need to depend on shops anymore. But I just don't have the tools needed to do some of this work. I also don't have the money for them. So I will have to deal with situations like this for a little while at least.