92 Corolla shifts too late

Hi all, I just put in a used(guaranteed) transmission in a real nice Toyota corolla and everthinbg went real well. However, it shifts to all 3 gears but late. First to second at 30 MPH and second to third at about 60 MPH. I have adjusted the throttle cable from one end to the other with no change. Does anyone have another suggestion before I rip this thing out? Is there a governor that could be bad or sticking? This is now the third one for this car and I am getting tired of swaping them out. Any help would be greatly appreciated. Russ

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Reply to
radarguy1
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Did all of the replacement transmissions shift late or just this one?

Have you taken tranny pressures?

Is the transmission ECT or conventional?

If ECT, I'd double check that the correct speedo drive gear is installed.

If conventional, I'd take a look at the governor.

Reply to
Ray O

Does your car have some 'power' button. Sometimes used to boost the engines performance, by changing the shifting points?

If so, I would start there.

hth,

tom @

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Reply to
The Real Tom

both of the previous transmissions shifted normally.

Idon't think I have the equipment to check the pressures nor do I have the instructions.

ECT is not a familiar term to me. I don't believe there was much of a selection for this particular car. either a 131L or 132L which also went into a Geo Prism and chevy nova.

Is the governor accessible from the pan?

One thing I noticed was in setting the throttle cable was that I could not adjust it far enough to get the cable nock out past the boot. Does that offer any clues?

Thanks, russ

Reply to
radarguy1

You would need a set of transmission pressure gauges to check internal pressures.

ECT is an electronically controlled transmission. An ECT has a set of solenoids that control shifting based on inputs like coolant temperature, vehicle speed, engine RPM, and throttle position. The solenoids are visible on the side of the transmission case and will have wires attached.

The governor is generally located on the output shaft of the transmission.

Sorry, my questions were based on AT's in general, I don't recall how the throttle cable connects to the transmission but here are some things to check if you still have access to the the old transmission:

The replacement should be the same exact model, i.e. 3 speed or 4 speed, electronically controlled, etc.

Also, make sure that the throttle cable is not kinked, and if the cable attaches to a lever, that the lever is the same length and oriented the same. My guess is that the condition is related to the throttle cable.

I've noticed that vehicles that tend to run through transmissions are regularly used for towing but don't have transmission coolers or the driver does not come to a complete stop before shifting from drive to reverse or vice versa.

Reply to
Ray O

OK, got all the lingo down and I did some more checking. I compared the throttle cables from my old tranny and the newer one. The older(shifted correctly) cable could be pulled out over an inch more than the newer cable. Some thing is stopping it assuming they are exactly the same tranny. We did check the VIN and they both came from

92 Toyotas. It is under warranty but if it were simpler to fix the cable than rip the whole thing out I would opt for that. I pulled the pan on the older one since it is on the ground and looked for the cable end. It is barely visable wrapped around a wheel that operates the valve. It looks like I would have to remove the valve body to get to it and I think that is beyond my expertise.

If you were curious about the first two here is why they failed. Number >> both of the previous transmissions shifted normally.

Reply to
radarguy1

Dropping a valve body is not a simple do-it-yourself job. It should be done in a clean environment and if you lose any check balls, you're in trouble.

I suspect that the replacement transmission's throttle cable is either the incorrect one or was installed incorrectly, making it too short. I don't have much more advice for you at this point, other than having someone familiar with automatic transmissions changing the cable or trying to rig some kind of cable extension.

Reply to
Ray O

The control unit or the vacuum would be suspect to me.

Reply to
Jeff Strickland

Jeff,

Another response with no factual basis.

Set both suspects free because neither one is guilty of causing late shifts.

Reply to
Ray O

Without any other information, either could easily be a problem. There are several other things that could be a problem as well, things that you explored in your posts to the OP.

Reply to
Jeff Strickland

Actually, the control unit could NOT easily be the problem and it is impossible for vacuum to be the problem.

In my experience with Toyota ECUs, whether fuel-injected, transmission, suspension, occupant restraint, etc., they have an extremely low failure rate. Speaking with a representative that examines the control units when they are returned for core or warranty replacement, most years, 100% of the ECU's have no problem and the replacement was not necessary. In 15 years at Toyota, I saw ZERO defective ECU's of any type. Additionally, a problem ECU will usually set an MIL. There is always a first time for everything so yes, it is possible but highly unlikely that the ECU is a problem.

Toyotas do not use vacuum to control transmission shift points so it is impossible for vacuum to be the cause of the late shifts.

Giving advice to check obscure and highly unlikely scenarios or causes is a big disservice to the people asking questions, especially if the advice-giver's knowledge and experience is limited. When diagnosing a car, it is better and usually more productive if someone who knows about the car checks the most common causes first.

Reply to
Ray O

that's

It sounds like the "bellcrank" to the throttle pressure valve is hung up somehow. This is what the cable is attached to inside your 131L. The TP valve itself may be stuck in the max throttle position, the bellcrank may be jammed, or the cable knob may have twisted in the hole of the bellcrank. If further diagnosis confirmed this to be the problem, it would require the valve body to be removed to gain access to this valve and related parts.

Since junkyards always leave the throttle cable intact (unless they are morons) there's a good chance this trans has been fooled with. The trans typically doesn't/can't cause this to happen without some "help". You may simply have a binding cable, but I would think you would be able to detect that by feel. A quick and dirty operation of the cable should give you a clue as to it's condition.

If it's just a cable you could have a mechanic drop the valvebody and swap the cable for 2-3 hours of labor. It's important to keep the large valve body gaskets intact when doing so, or it will cost more time disassembling the various castings and installing new gaskets. The disassembly process is more difficult and requires careful reassembly of the retainer pins and check balls in exactly the right places. They will fall out when the castings are separated.

Toyota MDT in MO

Reply to
Comboverfish

Here is a follow up for those interested in the cause of my problem. I believe what happened is that when the guy that removed the transmission, he failed to disconnect the throttle cable before he hung considerable weight on it. I deduce this because after removing the transmission I inspected the cable and found that the sheath is supposed to be stuck in an adapter with a seal and then crimped. Well the cable was pulled out of the crimped section all the way until the sheath was actually loose and the adapter was broken below the crimp. Even if I could slide the sheath past the crimp, which I did, the broken adapter would have let dirt into the casing. My Mercedes mechanic(who got me this tranny) asked me to bring in the old and newer one. He was able to remove the good cable from my old transmission and put it in the new one without removing the valve body. It took 3 hands and a lot of dexterity but it only took about 20 minutes. The tranny is in the car and my son is now officially in training. ARG!! Thanks for all the help guys.

Reply to
radarguy1

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