GP1138 Posted April 11, 2020 Report Posted April 11, 2020 This 1992 STE is running great but has some small issues that I am slowly working out. The transmission shifts well and seems to put plenty of power down, but when I first start driving it after it sits even at the gas station, it starts in 3rd gear. I think I have a vacuum problem since I don't get air out of the vents but only on the floor, but everything I've read states that the vac modulator on the E trans does not control shifts, only firmness, so theoretically that wouldn't be my problem..? I'm going to grab a new modulator anyway I think since there was so much fuel running through the vac lines that it's probably prudent to do so, but could it be the reason I don't always start in 1st gear? Quote
55trucker Posted April 11, 2020 Report Posted April 11, 2020 Being an STE it should have the *2nd gear start* feature.....sure it's not activated? I take it that the FPR had failed? Quote
GP1138 Posted April 11, 2020 Author Report Posted April 11, 2020 Yes, the FPR was the reason it was running like crap, and once I replaced that it runs great with a stumble off idle every once in awhile. It does have the 2nd Gear Start, I can toggle the switch and the light comes on and off. I don't know if that light dead on indicates whether that is sending the 2nd gear signal to the transmission, so I don't know for sure if it's on and the light just isn't indicating it or not.. Quote
55trucker Posted April 11, 2020 Report Posted April 11, 2020 Off is *no light*, On is illuminated. Turn the switch off, manually pull the gear selector to 1st .........what happens when you drive away? Quote
GP1138 Posted April 11, 2020 Author Report Posted April 11, 2020 That's what I usually do. Sometimes it works, sometimes it doesn't. Once it starts shifting into 1st by itself, usually about 3-4 streets after I get in and start it up, it's fine. But off a cold start, it starts in 3rd. Quote
55trucker Posted April 11, 2020 Report Posted April 11, 2020 Engine temp shouldn't have any bearing on the trans ability to manually select a gear. Has the trans gear range selector been moved at all? Quote
GP1138 Posted April 11, 2020 Author Report Posted April 11, 2020 2 hours ago, 55trucker said: Engine temp shouldn't have any bearing on the trans ability to manually select a gear. Has the trans gear range selector been moved at all? Not to my knowledge. I haven't played with that, maybe I'll have a look. Quote
55trucker Posted April 12, 2020 Report Posted April 12, 2020 I take that you not familiar with the history of the car? You mentioned that you're seeing an issue with the HVAC, you're getting airflow to the floor, are you getting airflow up to the windshield, when the vacuum is completely lost the windshield is the default. Quote
Schurkey Posted April 13, 2020 Report Posted April 13, 2020 If the modulator isn't leaking, and the shifts are soft at low throttle, firmer, and higher-RPM at heavy throttle there's little reason to replace it. What does the fluid look like? How long has the filter been in place? Realistically, this sounds like a solenoid issue; but wire harness and the trans controller could be at fault. I've heard of second-gear starts when the spool valve in the trans valve body gets sticky. But the "E" trans use solenoids. Quote
GP1138 Posted April 13, 2020 Author Report Posted April 13, 2020 I might just do a pan drop and filter change and see what happens. Realistically, if it runs fine after that and just acts up when cold (like, the first couple of stops), I might just run with it. Thanks all! Quote
MemphisMan Posted April 13, 2020 Report Posted April 13, 2020 If you're having vacuum issues, I'd replace the transmission vacuum modulator. If it's bad, it will screw with the vacuum going to other components. It's a cheap and very easy thing to do before getting into the solenoids or changing the fluid and filter. I replaced the shift solenoids on mine, only to find out I had a bad modulator. I really wish I would've replaced it first. Quote
Schurkey Posted April 13, 2020 Report Posted April 13, 2020 40 minutes ago, MemphisMan said: If you're having vacuum issues, I'd replace the transmission vacuum modulator. If it's bad, it will screw with the vacuum going to other components. It's a cheap and very easy thing to do before getting into the solenoids or changing the fluid and filter. I replaced the shift solenoids on mine, only to find out I had a bad modulator. I really wish I would've replaced it first. Wouldn't it make sense to TEST the modulator, rather than making wild guesses and throwing parts? If the modulator isn't leaking fluid internally, it's not leaking vacuum. Similarly, trans solenoids can be electrically tested; but so far as I know, there's no way to test the fluid path that doesn't involve putting power to them and seeing if the trans shifts gears. I have a Kent-Moore "special tool" that's intended to do that--it connects to the bigass electrical connector on the side of the trans. The tech can then dial-up any gear ratio by spinning the knob on the tool. Point being, in most situations testing is better than guessing. But if testing requires equipment you don't have, at least make an educated guess by testing what you can, first. Quote
MemphisMan Posted April 13, 2020 Report Posted April 13, 2020 Just now, Schurkey said: Wouldn't it make sense to TEST the modulator, rather than making wild guesses and throwing parts? If the modulator isn't leaking fluid internally, it's not leaking vacuum. Similarly, trans solenoids can be electrically tested; but so far as I know, there's no way to test the fluid path that doesn't involve putting power to them and seeing if the trans shifts gears. I have a Kent-Moore "special tool" that's intended to do that--it connects to the bigass electrical connector on the side of the trans. The tech can then dial-up any gear ratio by spinning the knob on the tool. Point being, in most situations testing is better than guessing. But if testing requires equipment you don't have, at least make an educated guess by testing what you can, first. It wasn't too much of a wild guess my modulator was bad because I had a small amount of tranny fluid at the plenum side of the vacuum line. I just wish I would've known to check that first. Agreed that testing is better than guessing and having special tools are great when you have them. If GP1138 doesn't have special tools, he should investigate the modulator. I'm glad I did. The "experts" at the transmission shop recommended a full rebuild at the cost of $2100 using their special tools, but they were obviously after the $. Quote
mfewtrail Posted April 14, 2020 Report Posted April 14, 2020 Like Schurkey, I would suspect a solenoid related issue. This is the solenoid pattern for the 4T60-E(same for 4T65-E, 4L60-E, and 4L65-E as well). Range 1-2 Solenoid 2-3 Solenoid Park ON ON Reverse ON ON Neutral ON ON 1st Gear ON ON 2nd Gear OFF ON 3rd Gear OFF OFF 4th Gear ON OFF Quote
GP1138 Posted April 14, 2020 Author Report Posted April 14, 2020 Thanks all. I appreciate the info! Quote
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