Starts, idles, pulses dies...help???

[66sprint6]

Car runs like a champ, idles strong as can be and is alot of fun to drive BUT lately its been actin up when I start it. Itll start quick and easy, idle for a split second, then the idle starts huntin and it stalls out. If I keep my foot on the gas and giver her about 1500rpm for a couple seconds or just drive off it will idle just fine the rest of the drive, never coming close to stalling or idle hunting again till I start it back up again. I did a ton of searching around, figured it was the IAC. Cleaned it, nothing, replaced it with a Ford part, NOTHING!!! I cleared the computer and it fired up like a champ the first time and ran just fine, next time I started it she was back to the same old BS. I pulled my codes, got 11 (good) 67, 85 and 33. Im foolin with it tonight tryin to figure it out, as its only a minor inconvenience seein that she runs like a raped ape otherwise but Ide like to be able to start it like its EFI and not a carbed car LOL
Any ideas???
Thanks guys!
Matt

OH...mods = stock 5.0 with TFS1 cam, TFS Street Heat, full boltons except pulleys.

 

[jrichker]

Use of the search feature would have unearthed this gem...

See the "Surging Idle Checklist for help with all your idle/stall problems. The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.

 

[66sprint6]

LOL smartass ...but I one upped you and already have that saved in my favorites and have actually used it on a couple cars now...thanks for puttin that together and keepin it up by the way!

With that bein said, i already went thru that, hence the replacement of the IAC and pulling the codes (once again all thanks to that thread) but it still wont act right. Tonight I took the intake apart and cleaned the MAF and the TB and then took the EGR off and made a gasket with no holes in it to block it off eliminating a leaking EGR. She seems to run ok but the real test will be how she starts in the mornin. I guess I was just hopin that someone else who had similar problems would chime in with what worked personally. If the EGR doesnt fix it im leanin towards the new MAF ive got on there, cause I accidentally left it unplugged and started it and it acted similar till I plugged it back in and it idled a little better.

ANYone else have a similar issue? She idles awesome after that little deal is over, so its strictly on startup that it has trouble.
Matt

 

[ryan218]

check the fuel pressure. could be the fuel pump on its last leg.. i had what your describing with my old 5.0. did the same thing.

 

[jrichker]

I'm glad the Surging Idle Checklist has been helpful.

The initial stall and surge on cold start can sometimes be traced to a sticking IAC (which you have already replaced) or overadvanced timing (more than 14 degrees). Prior to a cold start, remove the SPOUT jumper from the distributor harness. Start the car and if it behaves properly, the timing is too advanced.

Make sure the base mechanical idle is set correctly, the Surging Idle Checklist has the proceedure.

 

[66sprint6]

Well crap, never mind. She ran good all day today then died on me in a parkin lot. Got it runnin just fine, but now its doin the same ole BS about not wantin to stay runnin when I start it, now it doesnt matter hot or cold. One thing I noticed was that when I pulled the vacuum line off the Fuel Pressure Regulator, capped and uncapped it ran the same. When it was leakin vacuum there was absolutely NO change in idle or how it ran. Does this point towards a decently massive vacuum leak somewhere??? Im gettin frustrated...i need a good day to sit down and test everything and figure out what the heck is wrong here.
Matt