Randy, what's the model number of your Innova scan tool?

 

It's a Innova 3140.
Let me update you what is new. I went to fill up with gas yesterday and the darn thing spewed gas all over the place once it filled up. The garage that replaced the fuel pump for me obviously didn't get it right. So I took it back to them and stood there while they dropped the tank. We thought one of the tangs was preventing the fuel pump housing from seating properly so the mechanic re-installed it and again, it spewed gas all over. I have ordered a new tank and upper/lower fuel filler necks and a new vent valve.
If the pump was changed and yet there was a leak at the top, could this still have in all theory prevented the tank from pressurizing correctly?

 

The tank does become pressurized, but it's a negative pressure, (Vacuum). It will have positive pressure if the fuel expands. The PCM applies vacuum during the EVAP monitor, and during canister purge.

I looked through the manual for your Innova...will it allow you to view camshaft retard?

 

no, so I have to find someone that has the capability. I asked 2 guys that have shops and they had never heard of it. 8-) So I plan on taking it to a small GM dealership in the next couple weeks to have a full scan etc. done on it. It has a hole in the muffler also so could that be the issue? loss of back pressure or anything?

 

Never heard of it???? It's part of the job when you reinstall the distributor on 1996 or newer 4.3L Don't tell me they've never replaced a distributor on one

Exhaust will not affect it. The PCM does not monitor exhaust backpressure.

 

yea, thanks to you I realized who I was dealing with at these shops. They thought since it was only one position that that was the end of the story. I watched a video on youtube that showed me how they were monitoring everything so basically, I just got to scarf up some funds to let the pro's handle it from here. I'll post back once I get it handled towards the end of next week. Happy Easter everybody and thanks for all the input! I have already learned a ton about the Blazer! 8-)

 

Well, I now have a gas tank that does not leak, a new upper and lower fuel filler neck and a new AC Delco gas cap installed. The O2 and cat indicators quit flashing but b1 sw 3 seems a little sluggish so I intend to switch out all the Bosch O2's with AC Delco ones as soon as I find time to do so. The idle seems a tad bit better but the evap code is still being generated on the scanner. The check engine light is not on but being the type of guy I am, I like things perfect! I am going to give it a couple GM drive cycles to see if the code disappears in it's own since it is all brand new at this point. Remember, I have replaced both the vapor cannister and both purge solenoids. so the only thing I am thinking is that it could be the actual vacuum line coming from the motor on that purge solenoid that could be leaking somehow?
Idle is still surging but I will take to GM facility in the next couple weeks after finals to get the distributor cam retard set.
I'm making progress. The truck runs great other than the idle.

 

The downstream, (after the converter B1S3) sensor, monitors the catalytic converter efficiency. It has absolutely no affect on engine performance. It should indicate a fairly constant low voltage, around .45VDC or lower. The Bosch sensor should be fine there unless you're getting a DTC for it, (P0420). The other 3 sensors, (B1S1, B2S1, and B1S2) are all used for fuel control and all 3 affect engine performance. AC Delco and Denso sensors have the fastest reaction times, and Denso are typically less expensive.

EVAP: What DTC are you getting? Is it a hard fault or a pending DTC? There are several vapor lines in the EVAP system and a leak in any one or more of them will set a DTC. There's also a fuel tank pressure sensor in the tank/module that will also set a DTC if it, or its circuits, fails.

 

The shop I have it at now says that they have the cam retard set and that there was no change in the way it idles. They hit me for a AC delco cap and rotor when I had a new on e on it already. So, it is not in their opinion good to put die-electric grease underneath the cap to prevent arching as someone had suggested to me. LOL I can only laugh at this point because this thing is about to get some dieself fuel and fertilizer if you know what I mean! Seems like it is electrical to me but I am so sick of working on it at this point, I just want it back running right. sigh!

 

I agree, it will not prevent arching. Camshaft retard being set to zero degrees will prevent arching. The silicone dielectric grease is to prevent corrosion. It needs to be applied to the aluminum terminals, both inside and out, of the cap.