Hello Everyone .. So glad I found this site .. I need help!!! I have a 1995 chevy blazer 4x4 4.3 vortex . First thing that happened was my truck would not switch from 2 to 3rd gear, it was low on fluid 3 qts so I put 3 qts in still will not switch to 3rd. My truck runs rough getting about 8 mile to the gl. So I went had it checked by a computer at Autozone and this is what came back codes

PO 131,133,134,137,138,140,141,340 p1133 .

I also noticed every time I exit the truck it shocks me. Just wandering if I lost a ground somewhere in the system which would cause all fault codes and the switching from 2nd to 3rd gear sol switch 1, or 2 in tranny .

I replaced the Cat and muffler about a month ago , but it still has black carbon mixed with gas coming out of the tail pipe ..

Does anyone have a clue where i should start .. ????? Please help ..

Vance Morrison ,


Also just noticed a three prong vac hoses connector off from somewhere close to tranny .. its missing one of the vac hoses .. ### this may be the miss Im having !!!

 

Here is what all of those codes mean:I would look for a damaged wiring harness that runs down over the back of the motor and to the O2 sensors in the exhaust pipe before and after the catalytic converter. B1S1 is the upstream sensor which is located just after the 'y' in the y-pipe. B1S2 is the downstream sensor and is located just behind the catalytic converter.

I do not have the schematics for your truck, but you can also look for an O2 fuse or ENG1 fuse (both are used on the newer trucks as the wiring diagrams show in the OBD2 section) that may be blown although I wouldn't expect it to throw all of those codes. It looks more like a wiring issue to me.

 

Thank you ... I will look at the fuses first.. do you know where all ground points are for this truck. I'm wandering if a ground has come loose .. or even how to check if the ground is a fault?

 

Something I didn't say was when i changed the cat the old one that was on my truck had nothing in it.. It was hollow .. and I still have a slight leak of exhaust right before the cat ..I used the u bolts to and tac welded as best as i could but still has a leak in the exhaust .. would this throw the o2 codes? .. and the o2 sen before the cat has Tranny oil all over it.. I'm still thinking there is a loose ground somewhere because you want get a true reading without a good ground ..I could be wrong .. But that's why i posted on here because of the Pro's on here may have done or seen this in the past ....

 

Was there evidence that someone had removed the original catalytic converter prior to your experience with it? If not, the catalyst honeycomb could have broken up and found it's way into the muffler, but if you have replaced the muffler as well, that shouldn't be a problem.

Now, if you are still getting poor mileage, I would check the fuel pressure and see if you have excessive leak down. If the pressure leaks down more than 5psi over 10 minutes, you have a leak somewhere in the fuel system. The most common place for a leak is the FPR (fuel pressure regulator) followed closely by the 'nut kit' (internal fuel lines between the back of the plenum and the fuel injection spider).

I do not know where all of the grounds are for your truck. I still have a feeling that there is damage to the main harness that may be causing or contributing to your problem.

 

Thank you for the info .... I'm gonna start looking at the wiring and see if any is burnt broken are shorted out ..Thank you again .. Ive been on the verge of pulling what little hair I have left out .... lol ...

William