Thread: new help

been having an issue with a customers car ,has stock sr20det i think came from an avenir ...
now heres the issue whenever we start the car car if the water temp is below 120*F it idles normal and ignition timing is steady at bet.13-15degrees now after the temp passes 120*f the timing will jump to about 35* and the idle goes bet. 1800-2000rpm and it will surge ....if i should adjust the water temp , with NDS, below 120* all is back to normal ...
ive since check and changed water temp sensor and maf same result ...it is a stock ecu i am thinking thats the next possible part to change and see out come
any input would be appreciated
thanx

Have you changed out the ecu's temp sensor and what ecu are you running. The temp sensors have to match the ecu that your running. It definitely sounds like a temp sensor issue.
the ecu's temp sensor is the square plug one next to the single wire spade connector type temp sensor that is for the gauge. hope this works

i tried a different sensor in the there with same result ...could it mean that the sensor that ive tried is also bad? it wasnt new

Did you make sure it was the right one for the ECU.. You need to know if its a jdm ecu or a usdm ecu and then use the jdm or usdm sensor to match. You can test the resistance of your sensor also to see if its bad.

1. Disconnect engine coolant temperature sensor harness connector.
2. Check resistance as shown:
Temperature (C)[F] Resistance {in K ohms}
(20)[68] {2.1-2.9}
(50)[122] {0.68-1.00}
(80)[176] {0.30-0.33}

Did it work?

It is switching from the idle ignition table to the main ignition table.. this is why you are getting a huge swing in timing values. 15* which is the idle timing table values to 35-30* which is the main ignition table values.

Check your TPS closed voltage to make sure the ECU is registering that the throttle is actually closed!

Yeah, thats another good one. Definitely could be a tps problem. You should be reading roughly .42-.47 volts or so with the throttle closed, any more than that and its very likely gonna be causing this issue.

Ive seen improperly set tps sensors cause some wacky issues.

the tps wont register close unless it is at about .12volts or lower if i unplug the temp switch the idle stabilize but wont build boost .....as a matter of fact the car refuses to build boost no matter what ...if i change the airflow meter (i use the only one i could find but it was incorrectly match with the ecu) it build boost but was very rich , which was expected ...so i'm thinking the boost issue is maf related ...all help are appreciated especially jktuning seeing that you have a wealth of experience
thanx