[Shane Sloan]

Frustrated as all crap over here! I have a feeling I know what the problem is, but I'm looking for other ideas just in case. My 95 Bronco with e4OD almost always clunks in the middle of 1st gear. It doesn't feel like it's shifting into 2nd when it does it, but it may simply be a hard 1-2 shift. That said, it occasionally does do it, however very rarely, in other gears. When I bought the rig 3 years ago, it was having a derby level time of fishing for idle. I did replace the IAC and TPS, along with the shift position sensor. The idle fishing stopped, but the idle stayed high and the engine light has never not been on since. I recently decided to play with that, and bought the code reader. 122, of course. I back probed, good ground and 5v from PCM. Sensor reading was essentially non existent and no change when cycling the throttle. Just got a new Motorcraft TPS, and plan to put it on today or tomorrow. It didn't come with the collar, which bugs me as I've read that a bad one could also cause TPS problems. After 3 years, I have no memory of the condition (or existence) of the one I installed to begin with. I was annoyed that the idle has been at 1000 or just above since the original "fix," so I turned back the throttle stop screw. I got it down around 600 or so, but the truck ran rough and would occasionally stall at startup and initial reversing. I could not get it to find a spot in between 600 and 1000. It seems to like being in those 2 areas and not work properly in either one. Anyway, the hope is the replacement TPS will fix the problem. Just in case, any other ideas are welcome and appreciated.

 

[JBR14]

Does it clunk when taking off, like within a second or two of pressing the accelator. Or, does it clunk above 5-10 MPH?

 

[Shane Sloan]

It happens at different speeds in 1st gear. It can be above 5-10 mph if I get on it, but I don't usually get on it. Gas is expensive! lol! that said, it isn't immediate, as when a mount is bad.

 

[67galax]

U-joint or the slip yoke portion of the drive shaft needing lube sometimes causes a clunk when taking off from a stop

 

[Shane Sloan]

U-joint or the slip yoke portion of the drive shaft needing lube sometimes causes a clunk when taking off from a stop

It does have the original driveshaft. Despite getting rusty, part of the OE sticker is still on it. With the 35's and the lift, it seems to be in balance still, which is nice. My 94 didn't fare so well. I was looking at the desolate shaft, but I'm hoping it can wait. I did read on here, back when I was trying to solve this issue, that the yoke tends to hang up. Might have to bite the bullet. Cheaper than a transmission teardown and rebuild. To be honest, nobody in my area will even consider working on the transmission. They've all got new computers and seem to have forgotten how to work on real trucks. Had one of them refuse to do a tune up on my 88 Grand Wagoneer a couple of years ago. Napa service center says his guys don't know carbs. I asked why he hired them then. I was asked not to bring it back. lol

 

[Warthog4]

Sounds like you need to find a speed shop that works on older stuff. It is pretty sad how most of these guys are just reading the same computer diagnostics as we are, and throwing parts at it.

Have you checked the ECU? My high idle was caused by the computer. Once I had it rebuilt, the shifting got a little better too. I still need to have the PSOM tuned. If that doesn't fix the shifting, I will then have a shop look at the solenoids and diagnose further.

 

[Shane Sloan]

Does it clunk when taking off, like within a second or two of pressing the accelator. Or, does it clunk above 5-10 MPH?

Sounds like you need to find a speed shop that works on older stuff. It is pretty sad how most of these guys are just reading the same computer diagnostics as we are, and throwing parts at it.

Have you checked the ECU? My high idle was caused by the computer. Once I had it rebuilt, the shifting got a little better too. I still need to have the PSOM tuned. If that doesn't fix the shifting, I will then have a shop look at the solenoids and diagnose further.

Agreed. It's sad that car guys and girls no longer seem to have the love for the trade. I hope I'm wrong. Even more sad, I've already had it at a local speed shop. They build top fuel cars and always have a small car show worth of classics and square bodies in the parking lot to be worked on. I told them I needed a new rear main seal. I just don't have the room in my garage to do it. They first said they weren't sure. He checked and came back with 9 hrs in and out. Given the 2 other shops I trusted wouldn't do it, I said ok. Suddenly they were booked out 2 months. Central NY is as bad as you may have heard. It's a sad place for owning any cool rig. I dig program the PSOM. That helped with shifting in a big way. I haven't done much with the ECU. I figure if it still gives codes, it works enough for me to push that back and not damage it. Eventually all of it will be replaced. I hope to own it for many years. I really wish I could find a full harness, as I have found some green in some places. It would be great to rule out 27 year old wires

 

[Warthog4]

I had Module Experts rebuild mine. 2 day turnaround and good as new. No need to buy a new one.
Central NY is a pretty big area. I went to St Bonaventure. Know lots of people from Buffalo to Greece to Oneonta to Syracuse. That would be a tough place to own any sort of classic. FL is a little easier to find talented mechanics, at least my area is.

 

[Shane Sloan]

I had Module Experts rebuild mine. 2 day turnaround and good as new. No need to buy a new one.
Central NY is a pretty big area. I went to St Bonaventure. Know lots of people from Buffalo to Greece to Oneonta to Syracuse. That would be a tough place to own any sort of classic. FL is a little easier to find talented mechanics, at least my area is.

I just spent 8 months in the Tampa Bay area. I really wanted to get it down there, but I had to tow a camper and transport for the Bronco was 1100 each way minimum. Wanted really badly to cruise it in Clearwater Beach

 

[Warthog4]

I am in Clearwater, but just the other side of Tampa off 275 and Ulmerton.
I have a 1979 CJ7 that I cruise the beaches with. Once I get my roll bar and soft top, the Bronco will take over.
It is a little more fun to drive, a lot more work (so far), but a lot better for a family cruise.

 

[Shane Sloan]

I am in Clearwater, but just the other side of Tampa off 275 and Ulmerton.
I have a 1979 CJ7 that I cruise the beaches with. Once I get my roll bar and soft top, the Bronco will take over.
It is a little more fun to drive, a lot more work (so far), but a lot better for a family cruise.

I know the area. I miss it, but I have to admit I like not having my face melt at 7:30 AM! I did keep my eye out for a reasonable Bronco or square headlight wrangler (seems there were tons of that style on marketplace) but we were never sure how long wee would be there. My wife is doing contract work, helping the COVID in hospitals. She's on to Miami, and I had to bring the kids home for school. Never got to buy my toy. lol!

 

[miesk5]

Yo Shane,
I understand that you have the code reader.
E4OD Transmission Control Indicator Light (TCIL) is the LED with an overdrive on/off switch at end of the Transmission shifter stalk; flashing OD light is an indication of a transmission related trouble code in the Powertrain Control Module (PCM).
The transmission control switch is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module (PCM) (12A650). The powertrain control module then energizes the transmission control indicator lamp and the coast clutch solenoid, applying the coast clutch to provide engine braking and cancels fourth gear operation.
Does it cause the lamp to glow?
The TCIL indicates overdrive cancel mode activated (lamp on), electronic pressure control circuit shorted or monitored sensor failure (lamp flashing).

Rolling Idle; Table 6

Iggie Scope Engine for now to save $
Quick Test is Test for Diagnostic Trouble Codes
ISC-BPA is the Idle Air Control Sensor;

Vacuum Leaks; See my Vacuum leak test in post #11 @ Help with dtc codes and idle

 

[Shane Sloan]

Yo Shane,
I understand that you have the code reader.
E4OD Transmission Control Indicator Light (TCIL) is the LED with an overdrive on/off switch at end of the Transmission shifter stalk; flashing OD light is an indication of a transmission related trouble code in the Powertrain Control Module (PCM).
The transmission control switch is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module (PCM) (12A650). The powertrain control module then energizes the transmission control indicator lamp and the coast clutch solenoid, applying the coast clutch to provide engine braking and cancels fourth gear operation.
Does it cause the lamp to glow?
The TCIL indicates overdrive cancel mode activated (lamp on), electronic pressure control circuit shorted or monitored sensor failure (lamp flashing).

Rolling Idle; Table 6
View attachment 184793
Iggie Scope Engine for now to save $
Quick Test is Test for Diagnostic Trouble Codes
ISC-BPA is the Idle Air Control Sensor;
View attachment 184794

Vacuum Leaks; See my Vacuum leak test in post #11 @ Help with dtc codes and idle

The O/D button has always seemed to work as expected, and I haven't seen it flash. I does light up when pressed. Now, as for vacuum...that could be another story all together. You actually did respond to a question I posted about silicone line size a couple of weeks ago. I have to get those ordered. Most of the lines seem OK, but some not so much. I've replaced as I find cracks or they fall apart in my hand, but doing the whole bay is not exciting for me! I'll be doing it soon, but I hear no hiss, which means with the little time I've had available lately, it might take longer than I want it to. The soup can looks like it's about mid life. No noticeable holes and it didn't change idle when I sprayed it with starting spray. She's an ornery cuss, for sure.

 

[Shane Sloan]

Final update: Replaced the TPS with a Motorcraft unit. Problem solved, along with a few others. I have a passing gear again, and the idle is no longer stuck at 1000+