lockup quit working
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There is some pretty basic stuff here, the ECM contols the lockup and when it kicks in and disconnects based on certain conditions.
You say you checked the brake pedal? Try disconnecting the connector to the brake light switch on the brake pedal. When you step on the brake pedal the torque converter will go out of lockup. If that is shorting, then it is sending the signal to the ECM to never allow it ot go into lockup. Try it and see if there is any difference.
I am very familiar with some of the chip coding on the ECM for an '87 with a TPI setup. What is in your wagon and what year is it? Assume probably a carb'd motor?
This is all relevant to the wiring and what sensors are involved here to help you determine what to do next.
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OK, so based on the engine and what it is from the ECM should be controlling the lockup.
If you disconnect the cable at the trans, it will never go into lockup.
Next test I would do is to remove the connection to the brake pedal. If for some reason the signal is getting from there to the ECM/trans that the brake has been depressed, then the lockup would not be engaged.
If there is not change from that, probably an internal issue with the trans which wiould need to drop the pan to see if the lockup solenoid is working when it gets the signal.
This is pretty simple straight forward stuff, nothing too complicated about the way this works.
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did it get disconnected?
mine likes to slip in my lock up converter when i coast at 40mph for long periods of time, otherwise its fine
mine likes to slip in my lock up converter when i coast at 40mph for long periods of time, otherwise its fine
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Quick question how can you tell if the ECM is bad? Can the chip be tested?
Thanks
Robert
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To answer you directly......well kinda!
The ECM has the MEMCAL which has the chip embedded on it from GM. Since this is not the original motor/trans in this car, I have to assume that this has the stock ECM, wiring, and chip installed and now it does not work (again, assuming that it was working fine when installed in this car).
Now to actually test the chip, you would have to remove it from the memcal and put it in a burner, then read it with the appropriate conversion program then you could see if the data looks good.
The one thing with this particular issue is that I am assuming that there is no "Service Engine" lite on and no other aspects of the vehicle not running correctly.
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It's all original 1987 one of my sensors both wires were touching and now I'm pulling codes 43/45 and all my sensors have been replaced so I thought it may be the ECM was shorted? Also I just put in a new 350 motor to spec. that will work with all my old 305 parts that all are less than a year old. I have about 500 mi. on the new enging and the wires were crossed during the swap. Check engine light does come on when driving on the freeway. The wires wernt crossed they were touching each other. also I hooked the battery up backwards for a second and a little smoking occurred but everything seems to be o.k..
SORRY WOODY FOR INTRUDING ON YOUR THREAD.
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Should not have affected the ECM, but you never know. What ECM do you have (Part #)?
I have a few spare ECM's laying around and you might want to try another one to see if it clears the codes. In an OBDI system when the issue is cleared, the then code should go away. Might also be because of the 350 motor. Are all the sensors the same parts as the 305?
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I had the torque converter clutch solenoid fail but have no idea how to test it:dontknow:. Perhaps someone with more know how can advise you.
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before clearing the codes it pulled a 43/44/45 then I cleared them and had the one flash with the two following only then went for a drive and pulled the 43/45 so does that mean it's working correctly? I will get the number after work. I have the timing set at 8 btdc would that make it run rich? yes all the sensors are off the 305 I heard I may need a new chip or it takes awhile to remember the new settings? The one sensor I didn't change was the firing spark sensor.
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I would assume that if it is reading the sensors and putting out new codes, then the ECM is working correclty. But then again, that is an assumption!
It's working, correctly, not sure.Yes, when vehicles cycles (starts, runs, shut off....etc...) over and over, the ECM "learns" the parameters and keeps these. Now these have to be within some guidelines as set originally for each sensor, but it does get "smarter".
When you lose power to the ECM for any extended amount of time or clear it, it starts from scratch again.
You should get the right sensors for the 350, or at least check to see if you need different ones. They might be the same?
Get me he part number off your ECM and I'll see if I have one. Get the four digit alpha code off the MEMCAL as well. This could be part of the issue with the codes, wrong chip in the MEMCAL for the setup.
As far a timing, you got me? What does the 305 call for and what does the 350 call for a stock spec's?
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