I replaced my valve cover and plenum gaskets On my 1991 toy 4x4 3VZE 3.0 and i put everything in its right place and it sounds good but now the engine light is now on, i've rechecked everything, i've run out of ideas and don't know what to look for anyone had this problum ?

thanks for the help

 

Getting your codes from the computer would be the best place to start determining why the engine light is on. Download FSM (link in my signature), and follow diagnostic procedure for the codes you find.

 

thanks i will do that

 

i can't find any wear that could read the toys code

 

I found this link helpful http://www.4crawler.com/4x4/CheapTri...es/index.shtml

 

Thank you!! nerdlip this is a big help

 

code 52 Knock Sensor signal ?

 

Did you plug in the Knock Sensor plug on the drivers side valve cover area, just next to the #5 cylinder injector plug? If so, check the wires in that area. Brittle wiring in that area can be a cause of the lack of signal to the ECM, causing the light to come on. If there was no check engine light before you did the valve covers, more than likely you have a wiring issue.

 

You probably should have replaced the knock sensor pigtail while you had everything apart. They get toasty & go bad with all that heat from the engine. You'll need to pull the plenum/intake manifold back off (not the valve covers) to get to the KS pigtail. Costs about $30 from the dealer.

 

From what I have read of your posting, you did not have the intake manifold off, thus you did not mess with the pigtail or the knock sensor that are hidden below the intake manifold. Most of the time, a code 52 is a wiring issue. If you were doing the valve cover gaskets and the plenum gasket only, then look at the wiring from the connector next to the #5 injector back to your ECM. Testing this wiring with an OHM meter is the easiest way to tell if there is a short or broken wire somewhere in the bundle.
Do a search using the search button above on code 52, and you can spend hours reading all about everyone's fix for this issue.
"ENGINE KNOCK SIGNAL SYSTEM
ENGINE KNOCKING IS DETECTED BY THE KNOCK SENSOR AND INPUT AS A CONTROL SIGNAL TO TERMINAL KNK OF THE ENGINE CONTROL MODULE (ECU)."

 

thanks guys issue is fixed it came unplugged,and the pigtail is still good and flexible