transambill

iTrader: (1)

OK first The motor in question is a TPI 350. OK in town today while setting in park idleing the car looses rpm coughs and dies.
It fires right back up but dies immediately. after doing this a half adozen times it idles but I get maybe 12 feet and it stutters and dies and then the start and die routine again. I get it started and go about another 10 feet and it stumples and I feather the gas and it comes out of it and I drive it about 20 miles home without a problem. Now when you start it it will idle fine for about a minute then the rpms start going up and down from 200 to 1,000.
The car normally idels at 550rpm. Watching the fuel pressure guage with the crazy idle it go's back and forth from 32psi to 40psi,back and forth. this is with vaccume connected to the FPR. without vaccume it has 45psi. Within the last 8,000 miles I've added/replaced. New fuel filter,new injectors,BBK AFPR,plugs,wires,distributer cap and rotor. I have no idea how many miles are on the fuel pump or the IAC. I tried to adjust the IAC when I did the TPS but the car would not run with the IAC unplugged like the directions said. If I put the car in gear the up and down idle quits and it holds steady at 500rpm's also if in park I rev the motor up the crazy idle quits for about 1 minute then it starts out at a 2psi.,300rpm bounce back and forth and within 5 minutes shes back to the 32-40psi/200-1,000rpm bounce.Back when I set the TPS and tried to set the IAC it would not idle with it disconnected.It would start fine but immediately die just like it did tonight. I could get it to keep running if I staid on the gas and keep the rpm's at around 3,000 but it wouldn't even do that tonight when it almost left me stranded. I love working on my car and don't mind replaceing parts when I don't know how many miles are on them but then again I don't want to start replaceing parts at random hopeing to get it right. Does any of this sound like the symptoms of a bad fuel pump,IAC ,fuelpump relay or am I way off track here. I have a few more carshows to attend this year and I'm not ready to put her away just yet for the winter.
Almost forgot, Thru all this it's never set any codes. The check engine light hasn't come on once.

Vader

If fuel pressure holds at a steady 45 PSIG with no vacuum connected, but varies widely with vacuum, I'd suspect a problem with the regulator, not the pump.

bobsroc

I would concentrate of the no idle with IAC disconnected, that sounds like your problem to me. If fuel pressure is good with vacuum off, the pump and relay is good. If the car will not idle it is going to be hard to say its your AFPR with the other problems. Where is your base timing set? What dc reading are you getting at the TPS? Will the car idle better with the EST connector unplugged? EGR valve?

transambill

iTrader: (1)

OK I pulled the throttlebody off and took the IAC out and gave them both a good cleaning. Once everything was back together I checked the TPS to make sure I didn't get it out of adjustment. It's showing 0.544 on my multimeter and thats where I had it set at before so it's good. My base timeing is set at 8*BTDC. I pulled the vaccume line off my AFPR and smelled it and checked for gas indecating a ruptured dyaphram but no gas so the regulater checks out.I'm going to take it for a drive and see what happens.

transambill

iTrader: (1)

Will now it hasen't started bouncing but now when I start it,it cranks longer before it fires up and when it does fire up it shoots up to 2,000rpm before it dropps down to 800rpm. So now I've got to figure this out fast cause it's hard as hell sending a cold engine to 2,000 immediately after it starts.

transambill

iTrader: (1)

Update: I went thru the steps to set the idle or min. air. This time the car ran with the IAC disconnected,a little sluggish but it ran. I set idle to 450 ,shut off car,reattach IAC connector and EST. I start it and it jumps up to 1800rpm amd slowly drops down to 600rpm and then slowly starts to bounce from 400-1000rpm's. I shut the car off and disconnect the neg bat. cable for 10 min. then reconnect and take it for a 30 min. drive. Now it wants to jump to 1800rpm and slowly drop to 600rpm's and for about 10 seconds it will bounce from 400 to 800rpm's before settling at 600rpm's. and it stays there. If I shut it off and restart then the same cycle over again. Jumps to 1800 then bounces from 400-800 before stopping and staying at 600. Man this is aggravateing Almost as bad as the MAF BS I went thru last Spring.

bobsroc

Question, are you letting the car run for awhile after you adjust things, maybe take it for a nice slow drive, no WOT. The computer is going to need to relearn, so you need to give it a chance, As far as the motor starting up at alittle higher RPM then slowly working back to 600 RPM is normal. If your motor is pretty much stock, base timing at 8* advance is alittle high and could cause the hard start issue. Lots of guys say 6*, I set mine below that.

transambill

iTrader: (1)

My car rarely ever sees WOT. I use it for shows & cruise in's. When I took it for a 30 minute drive,it was nice and easy. It never got past 2500rpm's or 45-50mph. I live in the country and it was after dark so I took it slow and easy. I'm really paranoid that a deer is gonna step out in front of me and I don't need Bambie for a hood ornament. I'll lower my base timeing a little and see if it helps. It's been at 8* for over a year now and these problems just showed up out of the blue.

Vader

Bill,

I'm guessing that altering the timing at this point isn't going to help. Your symptoms sound more like a vacuum or idle air problem.

If you haven't already done so, you might want to remove the IAC, remove the pintle, clean and lubricate the stepper rack gear on the pintle shaft, lightly lubricate it, and reassemble it all.

transambill

iTrader: (1)

Thanks for the help. I think my problem lies with the IAC also.When I took it out I used carb cleaner and a toothbrush and gave the pintle and spring a good scrubbing. After cleaning it I was able to get the car to run with it disconnected which It wouldn't do before. That makes me think that before it was so dirty that the pintle wouldn't retract when I did the paperclip thing in the a&b terminas to set min. air,therefore when I unplugged it and tried to start the car the pintle was still out keeping the car from wanting to start and idle. I'm gonna try to pull it out and disasseble it like you said and clean it and see if it helps. Rite now the car is doing fine except the high idle to 2,000rpm's before slowly dropping down to where it's suppose to be rite after I start it.