I heard that the CPS does nothing in closed loop, my car barely runs when warm, but runs fine when cold, i also have changed the ect to work with my new wiring harness, my old ect was a pre 89 , and i have an 89+. I made sure the cps was lined up right, and i even tried moving the cps a tooth to the left and a tooth to the right, still didnt make it run well. can someone help me?
Who knows this?
- Thread starter pingerpar
- Start date
Well, you can pretty much ignore everything else that person says about the car. Unless that isn't what he said....pingerpar said:
The camshaft position sensor-CPS-tells the ECU engine position and speed. It has nothing to do with warm or cold.
Incorrect signal for engine temperature is being sent to the ECU, resulting in incorrect pulse width modulation.
Now we know why.
If the CPS or engine is out of time, the engine will run bad, warm or cold.
maybe this should help clear things up a little, my car is an early 89, the old harness was the original, but it had a connector that fit the pre 89 ect, i bought a new harness that is for my model year, the early 89 model, and i didnt want to hack the new harness up so i just bought a new sensor from Napa, probably not the best idea, but ill check the resistance and voltage coming from it, and there are no codes
Where on earth did you hear the CPS does nothing in closed loop?
First, get a timing light. Set your timing after the car is warm, as per the TSRM. Check that you have the correct timing set, and that you have the correct signal for coolant temp going to the TCCS.
You mention the ECT - Are you talking the engine coolant temp sensor, or the ECT computer for the auto tranny? (just verifying here)
First, get a timing light. Set your timing after the car is warm, as per the TSRM. Check that you have the correct timing set, and that you have the correct signal for coolant temp going to the TCCS.
You mention the ECT - Are you talking the engine coolant temp sensor, or the ECT computer for the auto tranny? (just verifying here)
Ok, I cleaned this thread up a bit, let's cut down on the chatter in the technical threads folks...
engine coolant temp sensor, do i need to put the jumper wire across the check connector? does change what your timing reads?
yes it does change the timming, when you jumper e and t1 it puts the ecu in test mode and sets timing to base timing, and here is when you check it, and adjust.
edit, i have done the same thing johnathan1 has done, remember to do proper testing so you dont replace a good part..
edit, i have done the same thing johnathan1 has done, remember to do proper testing so you dont replace a good part..
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So you had a pre-89 ECU temp sensor? But you swapped it out for an 89+ one?
If that's the case, I have done the same thing, and it works fine.
If that's the case, I have done the same thing, and it works fine.
You've moved your CPS around - I would first completely verify that your timing is correct. I had similar problems to what you had (ran great cold, sucked when warm) and found I was running 4 degrees ATDC.
Yeah, since the position and speed are primary inputs for calculation, that certainly can cause a drivability problem.
Failure to start is usually when engine and cam timing is way off, not just 4 degrees. Good point.
Failure to start is usually when engine and cam timing is way off, not just 4 degrees. Good point.
i measured the resistance of the cps last weekend, it was 225ohms for each pickup coil inside(spec 140-180ohms) would that do anything? ,also the air gaps were good, ill try all of these suggestions once i get home, thanks guys
something to add, the timing is right at 10 degrees with the check connector shorted like in the manual, another thing i didnt mention is the exhaust shoots out black soot droplets when reved high, and also my turbo sounds like the bov is going off when i rev it in idle, also, i have a kandN drop in filter that made the car louder when i put it on, but now it is a lot louder like it is building up boost.....NOW i have a maf sensor code and no cam sensor code, didnt touch the maf by the way, isnt the wiring to the maf cause of new harness, car idles good after a while, right when i hit gas pedal it studders, then revs high, then idles low and stalls. Help. lol
i unplugged my afm and the idle doesnt change at all, isnt that a bad thing?, when revved it doesnt detect the load, but shouldnt it idle differently?
Check the engine is at TDC before you put the cps in. Happened to me once. It happens to everyone once. jajajaja
either i am retarded and have it way off, or someone hasnt told me something on how to line up the cps, i lined it up with the cover off, at tdc, with the rotor a few degrees after the upper pickup, i also aligned the groove on the cps with the rotor of the cps how it says in the tsrm, so WHAT AM I DOING WRONG lol