Verify fuel pressure when it is acting up. You will need a gauge and there is a test port on the injection rail. You could tap in and run the gauge over the cowl and tie it to a wiper arm or tape it to the windshield. Correct fuel pressure is important and a must to verify.

I'm familiar with the Schrader valve test port you're talking about. I'll get a fuel pressure test gauge tomorrow and drive around with it under my wiper so I can read it.

Good point on the flywheel trigger windows, I had completely forgot about that until you mentioned it.

Any of the driveplates that have the windows can have the peripheral portion distorted too from a balance weigh welded on the outside of the converter getting pinched between this outer ring and the converter. This was a big problem on the 42LE in the Intrepid and Concord as well as the 42RLE in our other vehicles.



I re-read your post about the O2 sensor, yes it shares a splice with the OD solenoid wire - I have heard of instances that caused OD issues.

is it possible the downstream O2 sensor may be going bad, causing the fuel trim to mess up thereby causing the miss under load ?

Not really. The downstream 02 has very little to do with engine management. Its primary function it to measure the efficiency of the converter.

Lesson learned, don't ever buy a fuel pressure tester from Harbor Freight. Not unless you want a gasoline shower.

I'm still not certain that the one that I bought from Autozone after that is working properly, it gave me a reading of 38 psi (after bleeding the air out from the connection, twice). The reading before bleeding was 0 psi, even when running. It advanced to 39psi once I shifted into drive, and stayed there. It never fluctuated up or down with the missing. If this number is correct, it's alittle low for my truck, I believe. However, the truck never acts like it's fuel starved. No pinging going uphill and it's burning plenty of fuel right now, believe me. My guess is that I'm not able to bleed the gauge fully and it's not giving me a correct psi reading.

Also, yesterday it was fairly warm outside, the TC engaged, and shifted right into OD. OD functioned perfectly until the outside air temp dropped, then refused to engage OD. This was after climbing under the truck and making sure that both connections were on nice and tight on the trans. The Neutral Safety switch was not on very tight, so I pushed it down hard. It's telling that my OD engaged for a bit after this, when the temp was warm enough.

Nitrous, you were right. Holy crap is that miss amplified when in OD. The whole truck jerks alittle.

I will be checking the brake switch today. Googling what is meant by that, now.

Also, the truck has had a custom dual exhaust that connects to an x pipe for equalization. There is no catalytic converter, as far as I can tell. Same headers and exhaust for the last 100k. I just wanted to let everyone know, to eliminate the catalytic converter as a suspected culprit.

I will climb under and take pictures of the entire exhaust system is anyone needs them. The x pipe (the place where the pipes come together before branching back out into dual pipes) has a heat shield on it.

For what it is worth I have never bleed or heard of bleeding a fuel pressure gauge. Keep monitoring it when it is acting up.

I couldn't get these cheap gauges to read until I bled them at the connection port. I had to make them spray alittle fuel for a second or two to get them to register pressure. Unless I'm just not using these things right, that's their normal operation. You're using much better gauges, I'm certain.

The brake switch runs the stop lights. It’s an input to the SBEC for lockup and cruise control..

While in cruise the assumption is that once the brake switch gets used that you want to stop, so shut off lockup.
You are slowing down so you want lockup disabled to prevent surging/bucking/etc.

Most engine driveability issues are exacerbated by driving in a higher numerical gear or in lockup or in manual transmission apps with clutch engaged.
Lower torque multiplication in high versus low.


Temperature having the effect on your truck sounds like to need to look at that very closely. I’m not a driveability guy but cold temp should make the truck rich - what if any effect on the miss I don’t know. But 60-65 degrees engine temp or higher and you get OD, lower you don’t.

In regard to the temperature affecting whether OD engages or not, is this something that I should be tracking down on the engine side? Or should I be concerned that something in the trans is working incorrectly, sir?

I am going to change my thermostat, just in case it's malfunctioning and causing the engine to run cooler than it should.


Trans engaged TC lockup and OD perfectly all afternoon, because outside ambient temp was in the 70s. Miss is definitely something outside the trans, if my thinking is correct. This is a definite relief because I was still thinking I'd accidentally messed something up in the build.

Traffic was too heavy for me to use cruise control, will try tomorrow to check brake switch.

Any luck????

I'd been waiting on that pigtail adapater to come in so I could try what Transman said about switching OD and TC on manually. Learned a valuable lesson today. To not do business again with PATC. They say they mailed me a part, it never arrived, then said it showed back up at their warehouse and that I must have refused it. So I'm out shipping, and a restocking fee for a part that I never received. Their parts manager has been horrible through email, so I'm out 20 bucks and still don't have the part. Lesson learned, though.

I've just been driving the truck like normal. Some days there's a miss, other days there isn't. When it's warm enough OD and TC lock up. When it's cooler out, they don't. Cruise control doesn't work, no matter what I do to try to engage it.

I'm still thinking that this is a fuel pump or bad fuel issue, like I thought in the very beginning. The other parts were just coincidental, getting broken in the install. I haven't put any more additives in the tank and have just been burning fuel. The miss seems to be getting less with each tank. I've noticed that it likes to do it once it's warmed up and has been driven for 45 minutes. I didn't see anything on the TC when the heat shield was off, not even when rotating the engine.

I honestly don't know what to do but just keep driving the truck and seeing what happens. This is not a new truck, we're closer to 300k than 200k, so I can live with a miss after a freshly rebuilt transmission I guess.

O2 sensor will be getting replaced over the weekend, so maybe that will influence things. I'm sure the holiday season has been busy for everyone. Looking forward to being able to get it done after Christmas.

If the cruise does not work when the OD and lockup does then that is likely a cruise control only issue. I don’t recall all the requirements to achieve cruise lock, besides a Drive input from the N/S switch, trans speed signal, engine TPS, brake switch.

If OD and lockup does and so does cruise then likely you have an issue with a sensor or switch for temp. It should rule out the brake switch, N/S switch, speed sensor on the trans, the OD and lockup solenoids, engine speed input.

You still could have a wild TPS sensor showing wide fluctuation s in voltage.

Earlier you had asked about the temperature input. I’ll have to take a look at some paperwork and get back with you.

As far as I know there isn't a speed sensor on this trans, or if there is I don't know what would be reading the speed. I've got a N/S plug and the other three wire plug coming off of the OD/TC solenoids, and that's it. If the vehicle speed sensor monitors that, then I'm going to go ahead and replace it. I'd driven without it working for years so just have been ignoring it. I monitor my speed by rpms and sound. It's second nature now.

I would love to know more about how temp affects this trans, as it pretty much dictates whether I have OD and TC lockup, sir. I can't thank you enough for all of your help. This project scared me to death, at first, but now I'd tear another 46rh apart in a heartbeat and rebuild one.

Should be a speed sensor on the end of the speedo pinion adaptor. Maybe I am confusing years, instead of the cable there’s is a plug

Still looking for my paperwork -

If your PCM has a fault code or an absence of speed signal the trucks engine and transmission will not function correctly.

Sourcing speed sensor right now. I will report back once it's installed, along with any changes once 02 sensor is in place. Thank you Transman and Nitrous.

The truck didn't miss doing a grocery run today, so I got on the accelerator a bit when coming back home. Got up to 2500 in second gear before it shifted into third, nothing crazy. Truck missed every few seconds for the rest of the drive, after that. Shifts are perfect, outside of TC and OD, though.

I am going to swap the 02 sensor tomorrow hopefully. Weather has been bad down here (ok not lake effect snow bad, but rain and 40 degree weather still aren't any fun).

Installed O2 sensor. Here is what it changed.

1. Truck has noticeable power increase
2. Miss is still present after truck warmed up
3. OD and TC engaged normally after truck warmed up
4. Miss is definitely present during acceleration and OD engagement
5. Miss is VERY noticeable when OD engages, as Transman and Nitrous both said


The speed sensor should be here in a couple of days, and I will install and report back then.

Truck is driveable, operation is better, miss is still present. At one point the miss was hard enough that it felt like the truck wanted to backfire. This was accelerating from a dead stop at a stoplight.