91 vert fixed omp with a good ecu still in limp mode
#1
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91 vert fixed omp with a good ecu still in limp mode
i think the only challege i have left is adjusting the tps sensor. the original tps was bad so i found one off a turbo, and i have another one off of a 91 vert standard. i guess all i really want to know is if the tps is different for an automatic?
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ok, ok not real sure what codes im getting right now. It should be just code 18, narrow range, and the wide range tps code. I dont know cause im going to put in a new ecu.
I know my ecu is good cause ive opened it up and looked at it, it also came out of another car jut like mine. The original ecu was burned up and one of the chips was cracked. my original ecu is a n353 and the one ive got is an n352, im hoping that it's compatible.
i installed a new omp and i can clearly see it pushing oil so im guessing its good
I know my ecu is good cause ive opened it up and looked at it, it also came out of another car jut like mine. The original ecu was burned up and one of the chips was cracked. my original ecu is a n353 and the one ive got is an n352, im hoping that it's compatible.
i installed a new omp and i can clearly see it pushing oil so im guessing its good
#7
I thought my ECU was good initially until after taking a second look with a magnifying glass noticed a hairline crack (from burning out) running right up the Toshiba component that supports the OMP. The failure of this part from a bad OMP isn't as obvious as it first seems as I've come to learn.
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I thought my ECU was good initially until after taking a second look with a magnifying glass noticed a hairline crack (from burning out) running right up the Toshiba component that supports the OMP. The failure of this part from a bad OMP isn't as obvious as it first seems as I've come to learn.
Circuit boards don't always show any visible sign that anything is wrong. Chips go bad inside, all the time. Over heat, too much voltage, ect . IC chips are tough but they do fail - inside.
#9
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So you've only replaced the ECU?
You need to replace both the OMP and the ECU. If the ecu was bad, it was because the OMP killed it, just like it will kill your new ECU.
Replace the OMP with a good working one, and then replace the ECU with a good working one.
If you don't want to do that, block off the OMP, OMP injectors, and get a piggyback(Rtek) or Stabndalone (Megasquirt, microtech, haltech etc.) that you don't need to run an OMP with and premix.
When this happened to me, I bought a BRAND NEW OMP($1500) and got a good used ECU. I don't suggest that route. I should have just premixed and gotten a megasquirt, but I had different plans for the car at the time.
You need to replace both the OMP and the ECU. If the ecu was bad, it was because the OMP killed it, just like it will kill your new ECU.
Replace the OMP with a good working one, and then replace the ECU with a good working one.
If you don't want to do that, block off the OMP, OMP injectors, and get a piggyback(Rtek) or Stabndalone (Megasquirt, microtech, haltech etc.) that you don't need to run an OMP with and premix.
When this happened to me, I bought a BRAND NEW OMP($1500) and got a good used ECU. I don't suggest that route. I should have just premixed and gotten a megasquirt, but I had different plans for the car at the time.
#10
He's got another OMP, he's just not sure if the ECU is whacked out or not.
Regardless, it would behoove you to take molotovman's advice and get some type of system on there, such as an rtek, to allow you to get rid of the OMP and just premix before the same thing happens again.
Regardless, it would behoove you to take molotovman's advice and get some type of system on there, such as an rtek, to allow you to get rid of the OMP and just premix before the same thing happens again.
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No no I have replaced the omp. I'm pumping oil pretty good. I just need to know if the tps is the same from a standard cause mine is an automatic. I've got 3 tps sensors one off of a turbo, a standard and my old one. I've made a test light and tried to tune it myself but with no luck. I wanna drive this car so bad, I hate limp mode
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No no I have replaced the omp. I'm pumping oil pretty good. I just need to know if the tps is the same from a standard cause mine is an automatic. I've got 3 tps sensors one off of a turbo, a standard and my old one. I've made a test light and tried to tune it myself but with no luck. I wanna drive this car so bad, I hate limp mode
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See if you can borrow a Digital Multimeter from someone you know. Any Electrician or HVAC person should have one.
#16
Hey Will, you really need to pull the codes so you know what is causing the limp mode. You are really just guessing at the cause.
To restate, if you are in limp mode, there will be a code or several codes. Pull them, then you will know what is causing the limp mode.
Then you have a good place to start.
http://www.1300cc.com/howto/how2/codes.html
Good Luck!
And one more thing: Just because the OMP is pumping oil, that does not mean the OMP is good! The OMP will still pump oil if it has 'failed'. It will pump at what ever volume it was pumping at when the stepper motor stopped working. The electronically controlled stepper motor part only varies the rate of pumping. It does not pump the oil electronically. The pump is an electronically controlled variable rate mechanical pump.
To restate, if you are in limp mode, there will be a code or several codes. Pull them, then you will know what is causing the limp mode.
Then you have a good place to start.
http://www.1300cc.com/howto/how2/codes.html
Good Luck!
And one more thing: Just because the OMP is pumping oil, that does not mean the OMP is good! The OMP will still pump oil if it has 'failed'. It will pump at what ever volume it was pumping at when the stepper motor stopped working. The electronically controlled stepper motor part only varies the rate of pumping. It does not pump the oil electronically. The pump is an electronically controlled variable rate mechanical pump.
#18
The codes are read by the check engine light. All you need is this link. Instructions are pretty simple to follow.
http://www.1300cc.com/howto/how2/codes.html
#20
That maybe so, but in my case a quick visual of my ECM showed no such damage even though the circuitry for the OMP was bad.