Dirty Girl's stranded

[99sho-time]

No starting issue with that line off and nothing even plugged into it.

Ofc i check the lines and fittings for leaks. i then changed the solenoid. The only thing I concluded was the car for some reason is energizing the solenoid on start up i even changed the dpfe sensor. The car also misfires ALOT with the egr functioning. there was no lean codes nor was there ever any egr codes.

the line unplugged from the diaphragm doesn't cause a vac leak.

whats even weirder just now I hooked it up and started it just for kicks it started and stumbled..
And that's with the egr disabled in the tuning..

 

[E1]

Tuning is a double edged sword some times.

EGR malfunction + EGR CEL code turned off = big mess and no codes.

So it runs fine with green hose removed?

 

[99sho-time]

Yes and I've tried just about every combination of testing i could think of. if i put the tune back that has egr the starting issue is there and the EGR system is clearly causing misfires in park which makes no sense to me. no codes

 

[E1]

A disabled EGR is not a bad thing.

If the tune is in, and the motor runs well with the EGR unplugged, and there is no CEL, then life is good.

Obviously you want to troubleshoot and eliminate just for the victory, but at least now you can drive the damn thing.

 

[99sho-time]

Well here is where I get weird. I understand the amount of carbon buildup it causes. But in my opinion, the motor seemed a little bit smoother at highway with the egr working. but the misfire at transient speeds is bad. with my egr delete tune there is slightly more engine noise.

the gentleman who tuned it does not like egr deletes and didn't wanna give me a tune with one.
wasn't until it became 100% necessary

 

[98SF19]

You tried running it without MAF to check limp mode vs what it's doing now?

Yes, I took the whole airbox/MAF assembly off, leaving only the short intake hose attached to TB. Operations did not change, but I was able to hear how things shut down when normal intake flow began.

Eric and 99sho . . . good information here, I appreciate it. I just wonder if Doug's ok doing EGR-delete tunes.

To clarify, when you say the "little green hose" are you talking about the tiny one on top of EGR "valve" just aft of TB where big copper hose connects below? If so, mine is black. =) I replaced the DPFE on back of motor a few years ago as a result of a code (which it resolved), and the updated model had hose barbs rotated 90 degrees from original, and I remember that one of the hoses barely had enough give to get fitted and IIRC it got loose by itself at one point. When I get back to check PCM-CKP connection, I'll see if this is the issue at play.

the misfire at transient speeds is bad

without the transient speeds what joy in driving is there?

 

[99sho-time]

yes that greenish vac hose is the one that's atop of the egr diaphragm/valve. What i did was i got a dpfe with the same part # and watch to see if the one i installed had its voltage be in spec.

you should try unplugged the top of the egr valve and see how it runs/starts.

 

[98SF19]

This one? I do see a green ring at the end of the loomed portion.
So, what goes on behind the scenes after unplugging this that make much difference? Does removing vacuum from the diaphragm prevent exhaust flow and nullify the DPFE? Surely disabling the whole EGR setup is not that simple. I highly doubt this OR a motorcraft IAC will quell my woes, but I would very much like to be wrong here.
(this picture is about 8 years old, in the days preceding the powdercoat work).

 

[99sho-time]

yes that one pop it off before a cold start. nothing bad will happen the ecu will just compensate.

 

[98SF19]

No dice. Trying with green hose off did nothing, nor did also unhooking plug to DPFE (just gave me a p1401). I got a few codes I hadn't seen earlier - may have been my ignorance on the code reader and not deleting old stored codes. Under Enhanced DTC codes, I got p1100 MAF circuit intermittent, and p1101 MAF out of self test range, but this may have been from when I had airbox and MAF off. Also got a p1260 anti-theft, even though I hadn't seen the 'THEFT" light come on at any point during recent issues - again, probably old code. After clearing codes, KOEO test gave me back the p1504, IAC and p1000 OBD system not ready (or something) I will try to be more organized with codes next time to see if MAF ones come back when connected, but is the p1000 anything to worry about? Seems pretty generic.

 

[E1]

OK - Back to day 1 for your computer.

Take off the positive battery terminal and step on the brake pedal 3 or 4 times for a couple seconds each. This discharges the Keep Alive Memory. Basically takes the car back to January 1, 1998 for your computer.

It SHOuld clear any old pending codes but will reset the P1000 (not ready) code.

P1000 is set pending satisfaction of several test parameters (6?) that are completed during different types of test driving conditions. Sometimes it takes a couple days to clear P1000 but it shouldn't set the CEL. Once you have driven the compulsory tests, the P1000 should just go away on your code reader.

Now that we have reset the computer to day 1, the car may take a few moments longer at first try to start, this is common and can actually get scary on the early 96's. But once it catches, starting should go back to 'normal'.

Now run through everything again and see what you REALLY have in this critter, report back, and let's go from there with a clean slate.

 

[98SF19]

I always thought just disconnecting the battery and waiting 10 minutes or so would reset computer. Is the loss of vacuum after 1st brake pedal depression an issue? I suppose I don't need to really stand on it each time. After the rack popped a leak getting it situated on my driveway with no power assist after rolling off tow truck, I'm a bit hesitant to put more pressure than normal on the system. I did put about the same force as if I were braking moderately, and after repeating as you describe (with battery disconnected), the only codes that seem to remain now are the p1000 and the p1401 (DPFE still disconnected - DOH!). I'm curious what you mean by "this can get scary on the 96's - did it just take alot longer to get running?

Also, meant to ask this earlier . . . while CRANKING . . . should I see RPM gauge needle "wake up"? It's only coming up off zero once motor has turned over and is firing.

 

[99sho-time]

if your brakes cant handle a few pumps you shouldnt be driving it. he means that on the 96 the re learn process is a little rougher than the other years.

 

[98SF19]

The way I've seen tow truck drivers work my car's steering in engine-off neutral, I didn't think that would have ever caused an issue either, but low and behold, I do it and there's a leak (rolling turns only, avoiding full over either side).

As stated, I put some good force onto brake pedal, I just didn't know if the reset of computer relied on brake pedal travel, which you don't get much of after that first pump, no matter how much faith you have in the system. I'll give it a few days to get rid of the p1000.

Re: no RPM gauge needle movement during cranking . . . is this normal operation?

I've started making arrangements to trailer the car up to FPS. I think I've worn out my welcome at local shops and dealer (I can't blame them - just look at this thread! LOL), and anyway, they don't have half the experience that Doug does. I want to get some goodies for 3.5 EB as well.

 

[stephen newberg]

Yes, IIRC it is normal for the rpm gauge needle not to move during cranking.

smn

 

[98SF19]

I haven't been able to find but one source for the Gen 3 SHO Motorcraft IAC . . . part number is CX1658 and Summit is the only available source. They want $77 for it and I'm hoping to find it cheaper. I was surprised RockAuto didn't have any . . .

 

[gamefanatic]

Not that I see a big benefit to using an OEM version, they will likely only be used...

Here is one

 

[98SF19]

Thanks. In the expectation that the IAC won't be the clear solution, I may just order a Motorcraft through local store, as this would ease the return process. If it IS the solution, the price will be worth it as at least I can drive around enough to dump the p1000 and get trans warranty check-in for another year . . .

 

[98SF19]

After some research, it appears Delphi is the OEM for Gen3 IAC's. I was able to get one cheaper from Advance than from RockAuto (20% promotion along with SpeedPerks = BOOYAH). But in doing some Google research on the matter, I began to wonder if a VACUUM LEAK is the root cause of my issues. This was one of the things mentioned in the few sites I came across that caught my attention.

During some attempts to start recently, I've seen the red BRAKE light on, I think the right side of cluster. Would a loss of vacuum to booster kick this light on? It didn't leave any codes and I don't *remember* seeing it pop up in the dozens of attempts to start over last few months. Secondly, while getting to the PCM, I inadvertently put downward pressure on the two small vacuum hoses right behind the hi pressure power steering fluid line. It seemed that the small line going into the firewall made a slight hiss when I pushed it down a bit (this was with car off). I can't say if it was high pressure escaping or vice versa, but seemed to be a possible cause of vacuum leak. I think it would take a bit more than that to cause motor to die.
QUESTION: for the sake of eliminating this possible leak, is there any reason I can't just plug the large hose connection behind surge tank and see if motor stays running? I can't think of anything other than FPR that needs vacuum to keep running.

 

[99sho-time]

the brake ligth has to do with the parking brake and the sensor can become doggy. What comes to mind when I read this is you need to get your self a can of starting fluid and check for vacuum leaks. you can def isolate the vacuum system yes. take all the the vacuum stuff off and cap them. except the fpr