Hey all long time no see. Been around just havent posted. Anyways been having quite a few issues with the rig of late, outlined below:

P1388- bad asd relay or or wire cut somewhere on harness
P0135- bad front o2 (brand new ntk sensor) bank one, sensor one
P0138- bad front o2 bank one sensor two
P1281- engine to cold for to long, possible stuck open thermostat?


Anyone had these codes before and fixed them? What did ya do? I'm going to replace the thermostat with another 180* stat and see if that clears the p1281.

For the p0135/p0138 I got those codes after installing a magnaflow direct fit cat to replace my stock spoiled one. Replaced with brand new ntk sensors but still getting the codes? I've looked for a pinched wire in the harness but havent found anything yet. Gonna try and clean the connectors up and see if that helps. Could these codes stem from a stuck open thermostat?

With the p1388 , im gonna try cleaning the connectors up, and make sure the fuse isn't blown. What else can I do to try to clear the code up?

Now to the other problem , the trans has started slipping on one specific scenario. If I'm coming to a stop but have momentum behind me, see noone coming, so I hit the gas to get back to speed and it drops into neutral. Doesn't slip and acts just fine other wise. Gonna check fluid level shortly. I'm also getting a whining thats seemingly coming from the trans as well, really not sure how else to put it. Any help appreciated thanks guys.

 

The 135 is probably related to the ASD problem, as I think the O2 heaters get their voltage from that relay. If the truck runs though.... the ASD is at least doing most of its job. (it powers the injectors, and coil.....) Might be a wiring issue under the PDC.

138 is either a bad sensor (yes, I know its new.) or a bad wire somewhere. Those don't go thru the PDC, so that is a separate issue.

Putting in another 180 stat isn't going to help you. The 180 stat IS the problem. The PCM expects the engine to get up to 195, if it doesn't, it whines about it.

 

Thats a good point, didnt know the o2's went through the ASD. Truck runs just fine otherwise.

Been searching for a bad wire to no success so far. Wheres the most likely breaking point, any idea?

Yeah I've heard that, I decided to go with a 195* stat and just run my sct on a lower tune. Thanks HeyYou

 

I run a 180* and don't get that code. With electric fans running full blast I'm at 178*

 

I'm running at what appears to be 150-160 or so, which was pointing me to a stuck open therostat. Picked up a stant 195 gonna go back to that temp stat I think.

 

If it's a failsafe, rip the failsafe out. That's why I blew a head gasket before. Your truck runs one degree over operating temp, the thermostat locks open and overheats the entire coolant.

 

Its not a failsafe, its a napa brand one. Just as bad lol. Yeah its not good, hopefully gonna replace the thermostat tomorrow.

 

ASD relay code has disapeared. Been gone 3 days and hasn't returned yet.

Attempted to change thermostat today, got all the way to the damn thing but I can't seem to get the housing out from under the accessory bracket. Any ideas?

 

The whining would make me think that your trans is starved for fluid. I would change the filter. But if it is clogged obviously something is coming apart in your transmission to cause that.

 

Yeah I've heard that and I'm scared ive hurt something cause of it. It wouldn't shift into 3rd last night. 65km/hr , revving damn near 3 grand wouldn't shift. Drove 10 mins before it did. I'm pretty sure its toast