WOT Issues

[illSHOyou]

Some may have noticed that I recently replaced all my ignition coils with brand new coils. I thought all my low speed drivability would go away. The car certainly idled better, and I noticed the more positive feel of the engine when I put the car in drive. I still have a WOT hesitation but I discovered something today!

A year ago I was having trouble with the IMRC only working 2-3 times and then stopping untill I shut the car down and restart. I basically deemed the IMRC as faulty and discarded like everybody else does on this board.

Well...My SHO will only take off really hard 2-3 times and then turn into a dog. Shut the car off and start back up and it will take of 2-3 times and turn right back into a dog. So riddle me that?

I couldn't help but notice the PCM has control of these two situations and that the IMRC probably was never failed. The PCM just probably stoped commanding a signal after a short period of time...

Another interesting thing...when I push the O/D button the car downshifts but the light on the dash does not turn on. That light is controlled directly by the pcm. Could be a burnt out light, but really? A burnt out O/D Light...?

I am really starting to blame the PCM here folks...Opinions?

 

[illSHOyou]

Doesn't anybody have any ideas?

Should I try a MAF sensor?

Check this out...I just found this.
http://support.moates.net/2010/07/21/ford-tuning-load-with-failed-maf-tables/

This feels like what my car is doing. Jumping timing maps. Feels real good for a couple WOT and then feels like it went to a base tune low timing map...

 

[98SF19]

Did you open up the IMRC box to inspect? I went through 2 of them and each failed a different way. The first one's cable snapped, and the second one had the little delrin wheel crack (which I unsuccessfully tried to repair). Did you wire open your secondaries?

 

[SHOZ123]

Is the IRMC box still connected?

 

[illSHOyou]

Is the IRMC box still connected?

No, Box removed. LIM Gutted/welded holes/ported clean.

 

[illSHOyou]

I have verified a intermittent issue with the O/D Function. The car will downshift into 3erd with O/D off but sometimes will not illuminate the O/D light on the dash. I got the car to do this today after thrashing the **** out of if. Eventually I got the light to not illuminate.

To recap:

I have only owned the car for 1 year. When I first got the car the secondaries would only work 2-3 times during a key cycle, and then stop working.

I have a torque converter that does not lock at times when over 60 mph. Never has thrown our famous code. But locks around town no problem.

A O/D light intermittent work

WOT feels like timing removed/falls on ass/stumbles down low/then finally takes off.

Wouldn't you start to think that I might have a legitimate case to blame the PCM? or a damaged wire harness under the plenum tank?



Last I check the electrical diagrams the O/D light only has one wire lead from the PCM.


My buddies watch me cycle the key after the car started running like crape only to take off like a bat out of ****. Seems like erratic PCM issues.

Engine does not consume oil/no detectable blow by/doesn't burn oil. I am going to do a leak down test to verify if the engine is good, and make sure that its not a mechanical issue.

 

[illSHOyou]

Engine Health Check:

Leak Down Results:

Cylinder
1 3%
2 8%
3 5%
4 4%
5 8%
6 6%
7 5%
8 3%

Mechanically the engine is good! :woo-hoo:

15,000 miles on the used head gasket repair
Copper coated head gasket
Milled head .001
New Cut Down 2.5/3.0L Duratec bolts.

So, do i have a fuel problem or electrical...?

 

[Mr Anonymous]

There's a lot going on here but I'd recommend the following to start:

1. Drop your tranny pan and see how much junk is in there. Usually tranny and converter issues that don't cause a code are caused by broken parts in pan.

2. Swap the plugs and coils between cyls 8 and 5. I have seen more than one occasion where EFI/EMI from cyl 8 screws up the MAF and causes the PCM to get stupid where a key recycle can fix it for a while. If that doesn't help try swapping in a different MAF.

3. What year is your car? '96/'97 you can swap in ANY other '96/'97 SHO PCM and it will work. '98/'99 has to be re-flashed for PATS.

 

[illSHOyou]

There's a lot going on here but I'd recommend the following to start:

1. Drop your tranny pan and see how much junk is in there. Usually tranny and converter issues that don't cause a code are caused by broken parts in pan.

2. Swap the plugs and coils between cyls 8 and 5. I have seen more than one occasion where EFI/EMI from cyl 8 screws up the MAF and causes the PCM to get stupid where a key recycle can fix it for a while. If that doesn't help try swapping in a different MAF.

3. What year is your car? '96/'97 you can swap in ANY other '96/'97 SHO PCM and it will work. '98/'99 has to be re-flashed for PATS.

98 SHO

I found a bad coil. One of the brand new ones too. I cant believe how bad the car was stumbling and the PCM didn't even have a clue or throw a miss fire code for that matter.

As far as the transmission goes the pan was dropped earlier this year around March. Pretty clean in the inside. New filter and Mobil 1 syn ATF added to transmission. I intend on dropping it again next march for the same service.

I got some videos some videos I will try to load on. Not the best footage but it will show the car accel in 1st and the transmission shifting. The car really needs a tuner for the trans.

http://www.youtube.com/watch?v=f9q2SlfxLVg