Ugh....issues out the wazoo! HELP!

[94gtfreak]

Ok folks....I purchased a 1993 GT automatic (http://www.stangnet.com/mustang-forums/threads/new-to-me-fox.853252/#post-8582860) Ad said it had an 'idle issue' guy told me he had replaced mass airflow sensor, idle air contorller, throttle position sensor, coolant temperature sensor, plugs, wires, cap, rotor, O2 sensors, EGR, fuel pump and computer. Car would start and run when I first brought it home. It was idling very high though (close to 1500) drove it around the block, acted like it was gonna overheat (it didnt) had no power then died. Fired right back up but wouldn't stay running. Every time I started it, the car would backfire into the intake and die. Now I've checked timing, spark plug gap, wire order (all good) Car has cold air intake on it (no leaks) and didn't have a filter on it when I got it.

I was gonna do some electronic testing but I got to thinking that maybe it was the PIP sensor/stator and or the TFI module. So, naturally without testing crap I bought a new one. Stabbed the new dizzy and hooked up the new TFI. Started car to adjust timing and car backfired into intake then died. Went to try and start it this afternoon and battery is DEAD. There was nothing left on as the car has been sitting. I need any and all help I can get. KOEO and KOER tests are out of the question due to no juice. (did the TFI run down the battery?)

Sorry if this is choppy but I'm beyond frustrated between the car and reading the surging idle thread and others. HELP!?!?!?!?

 

[94gtfreak]

Pix of some (I thought) questionable connectors. Not sure if they're supposed to be hooked up to anything or not??

 

[2000xp8]

While i don't think your cold air is the problem, i'd still start by putting stock parts back. I know, you probably don't have them, but the tube, box, and a K&N shouldn't be much and in most mildly modified cases is superior to every cold air intake out.
Not sure what car your cold air was made for, but i doubt it was a fox.
What i see there is a mess and that's never good for idling.

Borrow or buy a battery charger, so you can code test.

Unplug the meter and see if the car will run better, once you get the battery charged.

 

[Mustang5L5]

Well, egr vac line is broken, so that's not gonna work.

 

[Boydster]

Start with the basics. Get the battery charged and get the KOEO codes.

As for the pics, I see a few things, but mostly emissions & vacuum related. Go back to the intake manifold and disconnect / cap off everything vacuum except Fuel Pressure Regulator, PCV Valve and Brake Boost. Make sure those 3 vac lines are tight and in good condition. Get the engine running like this then work on bringing those other systems back one at a time.

Last pic... The 2 wires that are crimped together... black with white stripes? I'd be finding what those go to as many of the sensors on the engine that are responsible for it running well use that black/white wiring.

 

[Doomstein]

Well, egr vac line is broken, so that's not gonna work.

^^
I noticed that little guy too. White EGR vaccum line is snapped.

 

[jrichker]

Two black wires with a white stripe... most likely the computer power ground. It is the second most important ground in the whole car. For some strange reason people think grounds aren't important in automotive circuirts. It isn't true guys...THEY ARE IMPORTANT...

The battery common ground is a 10 gauge pigtail with the computer ground attached to it.
Picture courtesy timewarped1972

Correct negative battery ground cable.

3.) The computer has its own dedicated power ground that comes off the ground pigtail on the battery ground wire. Due to its proximity to the battery, it may become corroded by acid fumes from the battery.
In 86-90 model cars, it is a black cylinder about 2 1/2" long by 1" diameter with a black/lt green wire.
In 91-95 model cars it is a black cylinder about 2 1/2" long by 1" diameter with a black/white wire.
You'll find it up next to the starter solenoid where the wire goes into the wiring harness.

 

[txstang84]

After you do all the above mentioned, see how those MAF sensor wires are spliced...any PO splice, to me, is suspect.


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[foxbodymike87]

i would undo those MAF wires and see if there still connected.

 

[VibrantRedGT]

Looks like many of your idle and stay running issues is that bootleg MAF wire job. You're braver than I am, just looking at the few pictures posted I would have walked away. Plus it's got a 20 year old Automatic. You didn't drive the car before you bought it?

Take the TPS off and see it the little tabs are there. I had 3.99v on the Tweecer, tried to adjust the TPS, wouldn't budge off 3.99v. Picked up, both tabs gone. Bought a new one, car idled like a champ.

Take more pics, I'm sure we can find more issues.

 

[txstang84]

Anything new??

 

[94gtfreak]

Thanks for the info guys. I won't be home till most likely Friday so I won't get to do anything till then. Will definitely check into that MAF wiring. I had just snapped the egr line before I took the pic too. Tps still has the tabs on it. Gonna try to set the voltage on it this weekend as well.

Looks like many of your idle and stay running issues is that bootleg MAF wire job. You're braver than I am, just looking at the few pictures posted I would have walked away. Plus it's got a 20 year old Automatic. You didn't drive the car before you bought it?

No, I didn't drive it. I high idled it around the block when it got home. I feel the car was a good deal. I don't have 'rust free midwest car with low miles and unmolested' kind of money. Besides, with any 20 year old car, I expect things to have issues. If the auto sharts out, I'll swap in a T5.

 

[txstang84]

Well, the issues you'd have with a well kept 20 year old car v. a neglected, modified, butchered, rigged, <insert adjective here> car are two different things. Yours is probably no worse off than many of ours were when acquired...mine was only 10 years old when I got it, and it was a basket case.

After you get around to checking/fixing all the above items, we look forward to hearing any results...

 

[foxbodymike87]

remember the TPS needs to be between .98 and .99 i believe.

 

[Doomstein]

And don't forget to re-attach that broken EGR vaccum line.

 

[94gtfreak]

Alright all. Fixed EGR, charged battery & readjusted timing. Car wouldnt fire. Disconnected MAF and car fired up. Half ass adjusted and car idled a bit high, but stayed running. Reconnected MAF sensor and car instantly died. I'm getting closer. I lost sunlight so I lost work time (no garage). Is it possible the MAF is bad? I figure the wiring is total though.

 

[Mr. Rustypwnz]

hey man, hit me up on facebook. I can help ya work on it if needbe.

 

[jrichker]

Did you fix the computer ground problem?

 

[2000xp8]

In my experience, unplugging the mass air meter and having the car run has been the meter itself.
Keep in mind, to get parts to test has never cost me any money, i can borrow pretty much anything for a mustang.

 

[94gtfreak]

hey man, hit me up on facebook. I can help ya work on it if needbe.

Will give ya a holler this weekend most likely. Doubt I'll be home this week.

Did you fix the computer ground problem?

I found the ground from your picture and its still connected. This appears more like it is supposed to be hooked to a sensor or??