Error codes finally.

I'm going to clean the MAF sensor with carb cleaner or brake parts cleaner & see if that helps.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Replace the Idle Air Control valve (IAC) You can take it off and spray it out with WD-40, carb cleaner or electrical contact cleaner then blow it out dry with compressed air. It should last you a little bit longer but it should be replaced every 15000 miles. Ford wont tell ya that though. the part is between $54 and $105 depending on where you go. I have cleaned mine twice and its on its last leg. I have to replace it soon. Definately replace it if you are having problems with it stalling out and dying on you at idle. The temp fix should get you by for a couple weeks maybe a little longer.

I'll look into that bro. I appreciate it. I'll clean it out & see if it helps the problem. If the problem does go away, I will replace it.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Both repair manuals I have say not to use carb cleaner (or any liquid cleaner) b/c it's an electrical component. But Haynes manual *also* says to use carb cleaner to clean the pintle if carbon deposits are there. Excuse my ignorance, but what's a pintle?

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Maybe I'm showing my ignorance here but what would that have to do with a misfire in a paticular cylinder?

Dave

(Tongue in cheek) Yeah, it sounds like your engine is leaning out enough to cause a misfire in cylinder #7. You might want to fix that. ;)

I think he told me check IAC valve due to the rough idle. I don't see how it'd help with a lean condition or misfire... but it isn't gonna take more than 10 mins & a multimeter to check it out, so I figure why not. I *am* going to clean the MAF today though.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

I cleaned the MAF sensor with brake parts cleaner... the wires were filthy. Now they are shiney silver again. I let it air dry & stuck it back in. I had the negative battery cable disconnected during all of this.. for about 25-30 minutes total. I also took off the IAC valve & it didn't have any carbon buildup.. so I just reconnected it without doing anything else to it. I also cleaned the IAT/ACT sensor with brake parts cleaner... couldn't really tell a difference since it's black.. but anyway... codes haven't returned yet.. I checked for codes w/ code reader anyway & no codes. The car idles far less rough.. and drives far less rough.. but it's still there. I've been tinkering with Cylinder 7 ignition wire a lot, so I'm gonna try to snag one from Tim. I'll keep you updated.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Pull the plug and take a look at it. It will tell the story or at least point you in the right direction.

Dave

If it ever stops raining I'll do that... what should I be looking for?

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Look for deposits and post back with the description and i'm sure someone can help. somebody once posted a link to a site that had pic's of the different depoists and what they meant. I may have it some where(i'm looking).

I'm not an automotive service tech, so this advice may be worth what you paid for it. :-)

For the most part, engines don't work correctly when there's a problem with fuel or ignition (or both). You're apparently having a problem with one cylinder, and a too lean condition suggests a problem with fuel. So you might have a dirty/clogged/tired injector on cylinder #7, but that's just a guess without looking at the car at all.

First pull the plug on cylinder #7 and make sure it's not fouled and is gapped correctly, and make sure the plug wire isn't arcing to the engine anywhere. I'd expect faulty ignition on one cylinder to lead to a rich exhaust condition, actually, but it's worth checking.

Also check for a loose hose or fitting, and rule out a vacuum leak.

I'd run a bottle of Techron injector cleaner on the next fill-up, but, if everything else is working correctly, you may need professional injector service.

A malfunctioning IAC will make the entire engine idle low/roughly but I doubt that it would lead to a lean condition on one bank only.

Good luck - Dana

Well... I pulled all 4 spark plugs on driver's side (cylinders 5-8 I believe) and they all looked the same. My buddy is a manager at Autozone (Stan) & he hooked me up with an ignition wire set for $50 w/ his discount so I bought 'em. I replaced cylinder 7 ignition wire & car runs like a CHAMP. These wires are also Ford Motorcraft 8mm wires.. but they seem to be MUCH better made than the old Ford Motorcraft wires.. wtf?? Anyway.. I only romped on it a little & the power is BACK. Gosh I missed it. I took it back home immediately though & parked it.. gonna replace the remaining 7 wires (I mean, why not? I paid for 'em!) tomorrow. Thx to all who replied.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Good advice, Dana.. and much appreciated. The problem was ignition wire to cyl. 7.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Well... I had nothing better to do at 11:20PM when it's 20 degrees F outside.. so I figured why not replace the remaining 7 ignition wires? Well.. I went out there & did it... idles like a purring kitten. Hammer on the gas & she ROARS to make her presence known... man it feels GREAT... instant smile on my face. =D

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Mike, on the old wireset, did you ever look for leaking electrons? At night with no lights around, i.e. pitch dark, pop the hood and look for flashes? It's one of the fastest, easiest things to do when having ignition problems. Sometimes you can see the problem.

i suggested to check the IAC because he said it stalls out, misfires, runs lean, and all were the same symptoms i was having. thats why i suggested to clean and/or replace the IAC, besides that it should be replaced every 15000 miles. thats what i have been told. havent seen it verified in a manual or anything though.

Yeah my buddy Stan (autozone) told me that little trick & we looked... sprayed water on the wires too.. couldn't find anything.

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch

Nah.. never stalled out.. but did run rough & ran lean. I haven't changed my IAC..... ever. No carbon buildup that I could find though... =/. I appreciate the advice tho!

-Mike

-- A happy kid behind the wheel of a 98 Mustang GT Cold air intake FRPP 3.73 gears Steeda Tri-Ax Shifter Flowmaster 40 Series mufflers (self-installed woohoo) Hi-speed fan switch