QuestionQUESTION: My daughters car was overheating. 102k miles on it. I had to do the following work on it..
Replace timing belt, water pump, timing belt tensinor. Spark plugs. Did compression test found one cylinder very low. Removed the head found a cylinder when a partialy melted piston. I removed all pistons took them to engine rebuild shop got 4 new pistons,rings,wrist pins back and assembled. I was carfull to mark everything at removale to ensure correct replacement. Put everthing back together. At the first starting engine cranked and idled roughly (i expected that). If i let it idle it would run untill temp gets to say 190 and then die. Then it wouldnt start untill the next day when cold. Through my home work ix learned then are 2 methods of setting the cam marks. One said to line the cam maks up, the other says to set the exhaust cam 1/2" notch below the intake cam. Anyway i have tried both several times now. Both ways produce the same. Hard to start, if started runs rough.. Im getting no dt codes at all. I removed sparkplugs, rigged them to ground, turn over engine all are sparking, injectors are spraying. Im a electronic tech all fuses, relays are good. I have replaced the "map, iac, cam, crank, fan radiator motor, battery. All grounds are connected. I could not find a correct wiring schematic for the car the online pdf i found do not match the color code or connector pin outs descriptions. The vin is "3C4FY48B42T319942" if that helps. The car has 2 computers. One is located drivers side up high above brake booster. I beleive this is the ECU' it has 2 40 pin connectors coming out of the left side of it as you look at it. The other is located driverqs side behide the front bumpper. I think It is the PCU. It has one long 40 pin connector..
What can i try next.
ANSWER: Hi Richard,
When you say you are getting no diagnostic trouble codes does that mean nothing is showing up in the odometer window when you do the on-off-on-off-on and leave on in 5 seconds or less, or do you get 'done'. If you aren't getting a 'done' then the codes are not being revealed.
On the timing marks, you start with the exhaust 1/2 tooth below, and when belt install is completed they should line up when the mark on the oil pump housing is at the trailing edge of the crank sprocket tooth timing mark.
You have ID'd the engine and transmission controllers correctly.
So let me know whether you are getting a 'done' or have a plug-in code reader and have a verified no fault code result as distinct from a no fault code readout.
I would wonder about the coolant temp sensor if it dies when warming up.
I have the '02 manual for reference.
Please read the PS below.
Thanks,
Roland
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QUESTION: I used a actron cp 9575 obd2 reader to ck for codes mainly, but i al so used the key on off on method also at present i get the "done" message when i try that. I will reset the cam timing marks to line up when the crank is at the trailing edge of the sproket tooth. The ohmnage of the coolent sensor at 90 degrees is 7.2k ohnms.
Since i wasnt getting any dt codes. To check to see if the control module was working i devised this test. I disconnected a single sensor at a time, then i turned over the engine, left the key in the "run" position. Then using the actron tool i would check and see if it registered a code. I repeted this for the " cam, crank, map, tps, iac, egr,oil pressure, " 2 of the sensors did not show up as a dt code. The " map, and iac" did not register a dt code for some reason. They have been both replaced since. I will go now and get back to that point. Just to make sure. While facing the crankshaftin in lorder to rotate it to set the timing you can only rotate it clockwise ( to the right) as you are facing it correct? And if you pass the mark go around clockwise 2 full turns to return to the correct tooth at top dead center. Thats what i have been doing. I well go and reset that. I will let you know what happens. Thanks
AnswerHi Richard,
Thanks for the additional info. Check to see if the coolant temp sensor resistance drops down to around 1k ohms when the engine is warmed up.
Another part to check would be the exhaust gas recirculation valve which is not totally 'monitored' by the engine controller, specifically is it closing tightly when at idle. If the valve stem is visible between the valve body and the vacuum operated top round piece, then try moving the stem via a screwdriver tip inserted in the slot of the stem. Spray some WD-40 on the stem where it enters the valve body and then move the stem some more to be sure it is closing tightly via the internal spring-action.
Checking all the vacuum lines that connect to the intake manifold would also be good to do.
You are correct as to the clockwise rotation of the crankshaft.
I would appreciate it if you would 'rate' my answers and consider giving me nominations for 'volunteer of the month'.
Thanks,
Roland
