I have a 86 pickup stick shift 4wd with 22re. Bought it with some issues and worked through most of them. I have a code 4 and 11 that I can not seem to fix. I replaced the TPS, checked and replaced the sensors for the cold start injector circuit, checked timing, checked injectors, tested egr, replaced IAC. When warm starts and runs ok but when been sitting for a while it takes a bit to get it going and warmed up. Any pointers / ideas?

 

Code 4, THW signal not getting to ECU. The ECU doesn't know it need to run the warm up enrichment.
Code 11, IDL switch not closed or AC switch on (while test jumper "T" in place)

You need to properly adjust the tps, maybe. And then figure out why water temp signal isn't getting to the ECU (broke wire, loose connection, bad ground ect)

 

Thanks for the reply! -

Code 4 - Good suggestion - I will trace and test the wire from the THW back to the ECU

Code 11 - The AC was removed on the truck prior to my purchase and there appears to be some connectors that were plugged into the AC set up that are hanging loose. I wonder if when the AC was removed is there a connect that needed a jumper or some sort of modification for the IDL switch. Any thoughts on that?

 

Code eleven only gets set if IDL is not closed (or the AC button is pushed) while in diagnostics mode (T grounded to E#). Don't make it complicated check the AC button, set the TPS, don't mash the throttle, see if the code went away.

 

Managed to spend quite a bit of time this weekend looking into the problem further.

Code 4 is fixed - after looking at the wiring to the ECU and being confused as to why the colors of the wire at on the THW did not match up to the schematic, I found out who ever had the truck before me put the IAC connector on the THW and the THW connector on the IAC - made an improvement with how it runs.

Code 11 is still there, however it DOES NOT come on when I start the truck, it only comes on about 3 to 5 mins after the truck has been running. I swapped out TPS and re-adjusted it, checked wiring from TPS connector to ECU and all looks good. This truck use to have an AC - everything from the AC was pulled out. Does the T connector the AC switch is connected to possibly need a jumper wire? Any other ideas? Appreciate everyones time and help here.

 

In search of help, Other than putting a new wire harness and or ECM into the truck, I am at a loss as to what is causing my Code 11 to continue to come on.

Code 11 is still there, however it DOES NOT come on when I start the truck, it only comes on about 3 to 5 mins after the truck has been running - seems like when power is applied / truck under load, which led me to think it might be the TPS I swapped out TPS and re-adjusted it, checked wiring from TPS connector to ECU and all looks good. This truck use to have an AC - everything from the AC was pulled out. Does the T connector the AC switch is connected to possibly need a jumper wire? Any other ideas? Appreciate everyones time and help here.

 

Ever heard of a wiggle test, wire broken inside its sheath, this is where you monitor the signal as close (at the ECU) sample point while physically manipulating the harness bundle.

Contact point inspection, anywhere the wire bundle touches something you need to inspect for wear thru the wire sheath.

Miss routed, under tension, wires shifting in the connectors.

Loose, spread, terminals in the connectors from someone jaming a meter probe into the connection.

Get a needle and release the female end of the connection from.the housing and snug them up with a pair of pliers so you have a friction fit with the male terminals.

 

Managed to make some time this weekend to take a good look at this. Pulled the harness out on the ECU side, unwrapped the wiring and sure enough found one broken wire and a couple of others that were rubbing - repaired them, re-wrapped the harness fired her up and looks good so far. Thanks for the pointers mate!!