In reference to injector. I replace all injectors with new ones as I did new ignition coils plugs and wires.
I ran car this morning and it idles little rough and still pops at 4k rpm's
I'm going to check IAC and MAF today
I bought both 02 sensors I'm going to change this too.
I was reading my shop manual and looking at wire diagrams. Looks like there are 2 sensors for temp.A CTS and a ECT. Looks like one is for computer CTS and other is for temp gauge ECT
I always thought the CTS did both computer and gauge.
Since many temp gauge isn't working in need to find the one wire ECT and replace it so gauge will work.
Any chance you know where on engine it is?

 

Isnt the ect sensor right up by the nose. Kind of by the hood latch area or a bit to the towards radiator cap? You can see the wire running around in that area. Not on the block if Im thinking of the one you are.

 

I know the CTS that is a 2 wire is under thermostat and a B to got to.
i changed that one but I'm thinking you maybe right!
It has to be somewhere to get emurged in coolant so it can sensor the temp.I have always found them on the block area or head.
When I look it up it always takes me to the CTS!
But that is only a 2 wire. BLK for ground and Yellow goes to the PCM and labeled CTS input on cpm.
Even AutoZone only shows a listing for the CTS
I don't understand that..
Now there is a low coolant sensor on radiator. Maybe that is same as the one going to dash gauge!
On wire diagrams it shows nothing going to PCM from temp gauge. Or vise versa!
Something has to connect to temp gauge to make a reading!
I'll check the radiator area tomorrow!
Thanks for your help..

 

Ok fixed problem,.. It was the short harness that connects to CTS and connects on top of front valve cover to main harness..
Crazy how when I took it off and ohmed the 2 wires BLK and the ylw it was fine.
I guess when it got hot it opened somehow.
Never seen that before.
Once I replaced it everything works now. Temp gauge and my fans are off.
I'm guessing my car even though I have a temp gauge it is all controlled by PCM..
Anyways thanks for everyone's help.I appreciate you all..

 

This car is cursed! After fixing the coolant sensor problem now when I drive it it won't go o we 40 mp and acts like it's starving for gas!
I need a cliff and a running start!!
This car is giving me high blood pressure
It keeps throwing PO304 and I can hear a tapping lifter off and on.

 

Fixed the PO118 and temp gauge is working.
but now I drive car and it bogs down when I put my foot on gas.Still pops at 4k rpm's
Is it possible the fuel pump is not working under load? .
If I keep rpm's over 1k no check engine light unless I let it idle at 750 then engine light comes on PO304 or PO300
Any ideas would be appreciated
Thanks

 

I was going to suggest the fuel pump thing but then why would it throw the code for #4? Maybe the fuel pump is causing the po300 but I wouldnt think it would cause the #4 code.

 

If I recall, contrary to believe P0300 is not random mis-fire, it is simply "mis fire detected". P0304 is telling you which cylinder. I know a bunch has been done, I believe new plugs, wires, coils, attempted testing of the ICM.... I don't recall if checks for vac leaks or injector checks were done. With the vehicle running, you can mist starting fluid around various locations with seals to see if that makes a difference in the idle. If you remove the #4 spark plug, how does it look? Any signs of burning coolant? Damaged plug? Improper gap? If those are Bosch spark plugs, I have had too many past bad experiences with Bosch in GM v6 engines. I would recommend AC Delco or NGK Platinum or Irridium plugs. Could try moving the injector to a different position and see if the issue follows the injector.

 

I replaced plugs NGK and plug wires also fuel injectors are new. I unplugged injectors one at a time to check the individual cylinders Every cylinder stumbled except for #4 it barley stumbled. But I don't see how that would make engine pop through exhaust at 4k
and when driving it cuts out if I Floor it.I was thinking fuel pump or fuel regulator but I did disconnect vacume line on regulator while engine running and no fuel present
I sprayed carb cleaner around where injectors are and manifold and no vacume leaks.
It's confusing

 

I agree, it is confusing. You have done a lot of diagnostics and toss parts at this in a way I would expect this to have been solved or at least understood. I hate to say, I am at a loss for a next step. But I am curious what the issue is.