Could Torque Convertor issue really be the GEM unit?

[98EXPY 5-0]

I bought my 98 Expedition at the end of 2009. I drove it for two months and only had two instances of what I had determined to be torque convertor shudder. I determined that from what I read online. Then I needed a bunch of work for inspection, and being broke at the time, I let it sit at my friend's house for almost a year (extra vehicle anyway). Now it's inspected and the shudder is horendous. I basically drive it in 2nd gear unless I need to go over 50, then I use DRIVE and turn the OD off.

I couldn't figure out how sitting for 8 or 9 months would cause the condition to get so much worse.

So I was thinking, instead of being a Torque convertor issue, I am wondering if it could be something else. Since it got 10 times worse, while just sitting behind my friend's garage for a year.

When I first got the Expedition, the first time I drove it in the rain, I had all sorts of weird things going on. Lights and clicking under the dash when the key was off. Thats when I found the windshield leak, and learned about the GEM unit and fuse panel issues associated with it.

The leak is sealed now, as far as I can tell. But could there be damage to my GEM or Fuse panel that would cause my tourque convertor like shuttering issues? Perhaps a dirty corroded contact that doesn't let the lock-up solenoid engage or something?



Another issue I am having is that my check engine light sometimes comes on for a while but goes out. Sometimes it flashes and sometimes it's steady, but once I come to a stop, it goes away. The guys at the parts store said they can't scan it unless it is on when they do it.

 

[Racenut]

As far as the Tq converter issue I have seen stranger so I would not rule it out just yet.

But then you mention having the CEL flashing at you at times. When the CEL is flashing, it means that you have a missfire on one or more cylinders but it is random and not steady enough to SET the CEL. The best thing for that is if you have a buddy with a scanner barrow it ( or pick up a cheap one ) and keep it plugged in the truck while driving, once the CEL starts flashing hit the scan button and see what it is reading.

All of your issues could actually be spark related ( including the shudder ) I would order all new coils off ebay from seller id UNEEKSUPPLY ($90 shipped for all 8 and they work great many people on here and also F150online use them) and then change out your plugs with MOTOCRAFT plugs.

These coils are famouse for going bad at +/- 100,000 miles or if they get wet!

 

[98EXPY 5-0]

Could the coils really cause the shudder? It runs fine through 1st and 2nd gear, then in 3rd gear I have to be above 2k RPMs or it bucks and vibrates like hell until I get it that high.

 

[99 Expy]

I am not 100% sure, but I think my uncles F150 had the similar problem like that and his coils were going bad, so its a possibility.

 

[Racenut]

Could the coils really cause the shudder? It runs fine through 1st and 2nd gear, then in 3rd gear I have to be above 2k RPMs or it bucks and vibrates like hell until I get it that high.

Under acceleration is when you need the most spark and if the coils are going out ( something is causing a missfire we know this by the blinking CEL) you will not have the power needed and the truck will begin to shudder, buck and jump around.

Think of it this way what happens when you are driving a little 4cyl 5 speed car and accidently try to take off in 2nd instead of 1st! Or if you go from 1st to 3rd with out running the rpm's way up, it will jump, and buck all over the place until the motor recovers or until you grab a lower gear.

same applies to the expy 1st and 2nd are ok due to the lower gear ratio's, but once you hit third and that higher gear ratio the motor has to work harder to get up to speed. So if you have week spark then it will run like crap and that is when you will see the blinking CEL for the missfire which will then give you that shudder feeling until the rpm's are high enough to smooth out then when it hits 4th it's the same thing all over again.

 

[walnuts4x4]

Could the coils really cause the shudder? It runs fine through 1st and 2nd gear, then in 3rd gear I have to be above 2k RPMs or it bucks and vibrates like hell until I get it that high.

mine did... horribly... and no check engine light on... finally changed all cops with ebay ones... I used global automotive.. same price as UNEEK... and autolite double platinum plugs without any problems

 

[Racenut]

? how many miles are on the truck?

Given the year I would say at least 100k?

Alot of people do not change out the coils and plugs for:

1. Ford says it dosn't need to be done until 100k
2. They are a bit of a PITA
3. If the old owner had heard the stories of plugs being "spit out" they may not have wanted to touch them out of fear and said it is still running fine so no need.

I have an '02 with 120K + and I just changed mine for the first time because the truck was running good ( or so I thought ) the new coils made such a difference it feels like it is brand new again! Not only the coils, but the plugs ( holy crap ) the factory spec on plug gap is between .052 and .054 the plugs that I pulled out ( original to the truck ) where at .074 and the electrode looked like this /| I had never seen a plug that was worn so bad.

 

[98EXPY 5-0]

This actually makes more sense to me than the transmission being the issue. The transmission ran 99% before it was parked. Perhaps even 100% is the two shudders I felt were actually one of the coils starting to go.

So a solid on CEL could mean anything, but a flashing CEL only means misfire?

I guess I have some ebaying to do.

 

[98EXPY 5-0]

? how many miles are on the truck?

Given the year I would say at least 100k?

The truck has 260K on it, but the motor has around 120k or so. I bought it from a Police Department, and their mechanic showed me the log book and the mileage of the truck when they got the new motor was about 140k. I also don't know how much was replaced when they did the swap. They may have just used the same coils from the old motor.

I thought being a police vehicle, it would at least have been serviced at regular intervals. However, I found at least one thing that shows me the mechanic just kept it running and probably put an inspection sticker on it when he shouldn't have. The front left brake pads were worn to the metal and the front lefts looked brand new. I thought the caliper was bad. Then I found the reason. The caliper bolts were rounded off inside (allen head), so it looks like he just never changed that side. Which also might explain why they only gave me three extra rotors with the extra parts they gave me.

 

[98EXPY 5-0]

All of your issues could actually be spark related ( including the shudder ) I would order all new coils off ebay from seller id UNEEKSUPPLY ($90 shipped for all 8 and they work great many people on here and also F150online use them) and then change out your plugs with MOTOCRAFT plugs.

It looks like his prices went up. $115 now, and $140 for the V-10 set. I might as well get them to have two extra, right? It looks like the same part number.


EDIT, it looks like he doesn't have any for a 98. Only 2004+