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93 gm tbi flashing 42 and 72 code
- Thread starter bad_bo_ti
- Start date
Find what the codes mean online...plenty of results from searching Google I would think. It's OBD-1 codes, will be the same for all OBD-1, or at least to the best of my knowledge.
Ugh...sorry, neither one of those means a THING to me.
Spark monitor probably means something along the lines of coil/module/etc. problems, output speed loss might mean the ECM is watching the engine RPM and comparing to vehicle speed, and its not matching what the ECM thinks the relationship should be.
However, I have never heard of those two descriptions for codes, so that is pure speculation. You are sure those are OBD-1 codes, not OBD-2?
Spark monitor probably means something along the lines of coil/module/etc. problems, output speed loss might mean the ECM is watching the engine RPM and comparing to vehicle speed, and its not matching what the ECM thinks the relationship should be.
However, I have never heard of those two descriptions for codes, so that is pure speculation. You are sure those are OBD-1 codes, not OBD-2?
i looked in my factory manual and those are the right descrption for the codes because he has a 4l60 E with it throwing a code 72 the tranny goes into a mode with maxium line pressure no TCC and soft landing second gear only it is casused by two successive speed readings have more then 1000 RPM(Difference must be more than 1500 RPM in P and N) This is word for word from the GM service manual on the 4l60-E
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dirtwarrior17
Banned
I don't know anything about this subject but wouldn't that mean bigger tires would make your motor run worse? seems like the ecm should be able to compensate.....
dirtwarrior17
Banned
the tranny goes into a mode with maxium line pressure to TCC and soft landing second gear only it is casused by two successive speed readings have more then 1000
Is there an english section in that manual?
Is there an english section in that manual?
ECM has to be told there is a difference. It has no idea the gears or tire sizes have changed, only that the output shaft RPM is XX, and XX RPM to the ECM means XX MPH. The ECM doesn't "see" vehicle speed from the wheel, that data is gathered before the differential. (again, tranny/t-case output) So anything changed after the tranny/t-case, the ECM can't "see" and has to be "told".
42. Fault at electronic spark timing circuit (sets when timing is set also, clear code and verify that it does not return.)
Have you set your timing with the wire disconected? If not it may be EST in the distributor.
Pull the batterey cable for a minute or so and reconnect. This will clear the codes and try again.
Have you set your timing with the wire disconected? If not it may be EST in the distributor.
Pull the batterey cable for a minute or so and reconnect. This will clear the codes and try again.
dirtwarrior17
Banned
that makes sense but what about the mechanical speedo?
what do you mean mechanical speedo a 93 would have a electronic speedo
Thunder
3/4 ton status
Code 42. Electronic spark control Circut problems. Either your magnetic pick up coil or possibly the dist module. Probabally the magnetic pick up coil. Its the round thing around the dist shaft. Have to pull the dist to change it out.
Code 72. No Vehicle speed signal. Check the VSS sender on the Xfer case it may have been un plugged. or is malfunctioning. The computer is seeing no siginal from it. Also I think this code can be set if you are running tall tires and dont have the right gearing not sure about that tho.
Code 72. No Vehicle speed signal. Check the VSS sender on the Xfer case it may have been un plugged. or is malfunctioning. The computer is seeing no siginal from it. Also I think this code can be set if you are running tall tires and dont have the right gearing not sure about that tho.
dirtwarrior17
Banned
I was asking because my rig has a mechanical with 35's and it ran great until i lost a main.
Thunder said:Code 42. Electronic spark control Circut problems. Either your magnetic pick up coil or possibly the dist module. Probabally the magnetic pick up coil. Its the round thing around the dist shaft. Have to pull the dist to change it out.
Code 72. No Vehicle speed signal. Check the VSS sender on the Xfer case it may have been un plugged. or is malfunctioning. The computer is seeing no siginal from it. Also I think this code can be set if you are running tall tires and dont have the right gearing not sure about that tho.
i will check the vss sender i did have the transfercase out of it 2 months ago (dont drive it that much) as far as electronic spark i think i will do as stated above, check timing them pull cable and resest codes and see if they come back. and maybe start looking for a different distributor. thanks, chris
K5MONSTERCHEV
1/2 ton status
Yes, 42 is EST circut. Either: the PROMs not seated, wirings bad, or the modules bad. I can tell you how to check it, PM if you want.
