Would the following trigger a CEL?:

vaccuum leak?
bad TPS?

thank you

 

Vacuum leak= probably not

Bad TPS= yes.

 

something wrong

 

After 02 senors, vaccuum check, plugs and wires (and a failed emissions).. the truck is still idle jumping and running poorly.. I thought I had it nailed but its back!!! So I have been reading alot about TPS's and thought I would inquire.. So if the TPs would trigger a CEL, and I dont have a CEL on, then Im cool?? I even rana scanner and pulled code 21 and 27..hence the 02 sensor changes... but nothing showed up about a TPS..

any thoughts?

 

Is your coolant full? When the idle in my '93 22re was fluctuating, it was due to low coolant.

 

There are several things but mostly anything that has an input to the ecm can set off a CEL.

 

Code 21 and 27 are.....?

 

You may be cool, but you can't really diagnose your problem that way. The computer is very smart, and if a sensor is way out of whack it will give you a clue about where to start looking. But the lack of a code only tells you that things haven't gotten so bad yet that the computer is complaining.

For instance, if your only TPS problem was an intermittent idle-position condition, I don't think that would throw a code. But it might give you loopy idle.

So you still have to be systematic, even if the computer doesn't know yet that you've got a problem.

 

Basically:
21- faulty heater circuit on primary O2 sensor
27- faulty heater circuit on sub-O2

I already commented on this on his other thread: https://www.yotatech.com/forums/f116...e-help-179698/

 

went back to emissions this morning after all that work done..failed bad!!! Legal CO limit is 1.20, I was 7.89!!!!!!! What in the hell is going on? Anyone know what that level is 7 times what it should be? the truck aside from the idle jumping from time to time, runs well.. What can I do to pass emissions????

thanks