help....yet another q' :)

[trinitykt133]

alrighty i know this has been posted in a sense on back a few posts but im gonna try this anyway... my 88 gxe is running rich. i baught a new o2 sensor about 6 months ago and it ran beautifully then one day my cylinder head temp sensor harness lost contact with the sensor (corrosion) i cleaned it up and i know its working again becasue when i unplug it it runs much worse compaired to when its pluged in. but ever since it first happened the car is running rich. if i go down the road the car runs with no power like its flooding untill it warms up. if i shut off the car for a while and come back out to start it up again and its still warm it does it even worse. i put the computer in mode 1 diag. the red light stays off but the chilton manual says it should only be staying off when the comp is in open loop. i know its going in to closed loop so it should be on i guess.... i tried mode 2 and when the car is cold the red light stays off and the only the green blinks meaning rich. but the problem is it took about 5 minutes untill the car was all the way warm before the red blinked syncronised with the green meaning the mix was right. thats about when the car starts running right going down the road. once they both work...at idle the lights do nothing. they dont blink at all untill about 2000rpm then they do work. it sounds to me the mix is too rich all the time and once the o2 sensor warms up its compensating. i have reset the computer over night and ran it for a while but it still acts the same. the chilton manual says the mix can only be adjusted at the nissan garage with "special tools" but if you guys know how to do it i'd be happy to hear suggestions
-matt

oh yeah ps my gas mileage is about 19.5-20 on country roads and highway mixed.

[Drjmaxx88]

Sorry to post a question to your question. How do you get to your CHTS? I mean you make it sound like its a snap. Mine has gone bad and I need to clean and plug it in.

If your gas mileage is still about 20mpg. Then the malfunction might be with the emission system. A bad PCV valve, bad vaccum hoses, maybe the vaccum is set up wrong. In my car the last owner rerouted it to run better. But when I started fixing it,it made no difference because the vaccum wasn't going the right way.
Also if your car has been running rich you may want to change your plugs, they're probably fouled because of the rich running condition.

[blackmaxima88]

The CHTS is on the front of the engine. As you're looking at the car from the front, this is the left-hand side where all the drivebelts are. A shielded wiring harness runs to it. I'm pretty sure this is the only wiring harness on this side of the engine. The CHTS screws into the head between the two camshafts.

Have fun replacing this. It is impossible to get to the CHTS unless you remove the timing belt covers, I think. you may as well replace the belt while you're in there, unless it's new. and if you're replacing the timing belt, you may as well replace the water pump and oil seals on the camshafts and crankshafts. Also, check out the tensioner and timing sprockets.

One thing leads to the other. Don't you just love cars?

Dan
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[trinitykt133]

i cleaned the chts when i replaced my water pump. its not as hard to get to as people make it sound. there are only a few bolts holding on the timing belt covers. it only takes about 30 minutes to remove the top set of covers and the mounting brackets to the tentioner pully which is also in the way. once you get that out of the way the chts is pretty easy to get to. if you are checking the connection to the chts then you only need to remove the top set. i had to take off both sets to change the h20 pump. the botom timing belt cover is a b***h to get off becasue you have to take of the main crankshaft pully with an impact wrench
just a suggestion but after i cleaned the contacts and reseated them on the chts i covered the conncetion with liquid gasket to keep moisture from corroding the connections again.

[Drjmaxx88]

thanx
I'll try it