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OBD II Not Connecting

Short story: PASSED

With the ECM communicating to my code reader, I took the truck in for Smog Test during my lunch. Chose a location in Santa Ana with the garage facing into the wind. They didn't even do a snap test. They spent an inordinate time looking for an EGR that my engine never had. They had a manual which said all 1999 and 1998 models with turbo had an EGR. Anyway, they passed it.

My back-up ECM arrives tomorrow.
Good to hear the news it passed.
 
I know all F series had no EGR or CAT only soot trap.

I told them that mine never had an EGR and I knew there was a model that did come with an EGR. Just didn't know it by VIN#.

Mine has an F in the VIN #. Which VIN # had an EGR?

Wondering why their manual just showed '99 with Turbo should have an EGR? Non-Turbo no EGR?
 
I told them that mine never had an EGR and I knew there was a model that did come with an EGR. Just didn't know it by VIN#.

Mine has an F in the VIN #. Which VIN # had an EGR?

Wondering why their manual just showed '99 with Turbo should have an EGR? Non-Turbo no EGR?
"Y" = L57 6.5 diesel VIN I'm thinking but Cali is weird w/emissions testing their manual is obviously wrong.

Here is GM's 1999 VIN decoder for other years just insert the year in the link string. https://service.gm.com/dealerworld/vincards/pdf/vincard99.pdf
 
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Another consideration is that Cali may have only allowed EGR equipped 6.5td's to be sold there new "not sure here" however I don't know what their policy maybe for used 6.5td w/o EGR.
 
Well this Biennial Smog Check causes considerable anxiety, but it's getting less and less.

This go around I pulled a blank on the reinstall of the Vacuum Pump. Just didn't need the bracket. I have two Vac Pumps, one installed on the bracket and one separated from the bracket. I kept reaching for the one with the bracket as the pulley surface was shiny from use. The separated one had a little rust on the pulley indicating it had not been used in a while. They're from my son's '94 and the '95 wreck. My bad.

Then there was the issue of no OBD II communication, a problem that was waived last time and I thought I had received a permanent waiver. But they've changed their computer system such that you can't pass go unless they can communicate with your OBD II.

The final issue is the snap test on the smoke. They didn't even do this test this time. However, when he shut it down and restarted it, the smoke definitely lingered more than 3 seconds. Thankfully, he wasn't looking at that as they were still trying to find the non-existent EGR.

They obviously cannot detect the tune, but they could fail it on the smokey byproduct. Thus my procurement of a back-up ECM reflashed with my VIN # and probably a real clean tune. One thing I did discover is that once you disconnect the ECM or the battery, it resets flags to zero and the ECM needs to relearn over a couple drive cycles. I had two short trips, back and forth when I took it in and it seemed to work. Article I read recommended a week of regular driving to fully reset these. I will put together a crash kit for the next go around and include notes.
 
Another consideration is that Cali may have only allowed EGR equipped 6.5td's to be sold there new "not sure here" however I don't know what their policy maybe for used 6.5td w/o EGR.

Yes this was purchased out of state and brought into California before they implemented Smog Tests on diesels 1998 and later. Lucky me.
 
Well this Biennial Smog Check causes considerable anxiety, but it's getting less and less.

This go around I pulled a blank on the reinstall of the Vacuum Pump. Just didn't need the bracket. I have two Vac Pumps, one installed on the bracket and one separated from the bracket. I kept reaching for the one with the bracket as the pulley surface was shiny from use. The separated one had a little rust on the pulley indicating it had not been used in a while. They're from my son's '94 and the '95 wreck. My bad.
I suggested the FORD electric vac pump as a cheap go-around that you leave and unplug when not needed, does Cali require vac pump to be engine mounted or?
 
I suggested the FORD electric vac pump as a cheap go-around that you leave and unplug when not needed, does Cali require vac pump to be engine mounted or?

They would know based on the sticker showing the routing of the serp belt. I assume that an electric vac pump has no pulley and thus gets no serp belt routing. That would get a fail.


Now that I know that I don't need the bracket for the Vac Pump (memo to file), it's just 3 bolts that mount it which makes it a 15 minute job to put it back on.

I will need to get a copy of a manual or specs showing no EGR for F VIN engines and keep that with my notes in the Smog Test crash kit.
 
They would know based on the sticker showing the routing of the serp belt. I assume that an electric vac pump has no pulley and thus gets no serp belt routing. That would get a fail.

Now that I know that I don't need the bracket for the Vac Pump (memo to file), it's just 3 bolts that mount it which makes it a 15 minute job to put it back on.

I will need to get a copy of a manual or specs showing no EGR for F VIN engines and keep that with my notes in the Smog Test crash kit.[/QUOTE
Perhaps FERM has it.
 
Perhaps FERM has it.

Woudn't know what to do without the FERM!

Now only if I could figure out my ABS fault. After this last electrical trouble shooting on the ECM, I'm sucking up the motivation to revisit the ABS. Last time I had the code pulled at a dealer, it said short in RF. But I had changed the bearing and installed two new sensors. I even tried the harness from the '95 wreck to the sensor. I put a multi-meter on the sensor plug and took an Ohm reading, but I don't know what I'm looking . I suspect it's in the wring, but I just don't know how to test the electrical stuff.
 
Woudn't know what to do without the FERM!

Now only if I could figure out my ABS fault. After this last electrical trouble shooting on the ECM, I'm sucking up the motivation to revisit the ABS. Last time I had the code pulled at a dealer, it said short in RF. But I had changed the bearing and installed two new sensors. I even tried the harness from the '95 wreck to the sensor. I put a multi-meter on the sensor plug and took an Ohm reading, but I don't know what I'm looking . I suspect it's in the wring, but I just don't know how to test the electrical stuff.
The ABS wheel sensor will have issues w/rust, I cleaned mine way back when I found GM had issues w/rust at front ABS sensor and sure enough it was only rust cleaned it up and used synthetic grease and it's been good since.
 
The ABS wheel sensor will have issues w/rust, I cleaned mine way back when I found GM had issues w/rust at front ABS sensor and sure enough it was only rust cleaned it up and used synthetic grease and it's been good since.

Well, I've changed the bearing twice, once after a water intrusion bearing failure, and each came with sensor installed and ither solved the ABS problem. Then changed just the sensor twice, and neither solved the ABS problem. Took it into dealer to have the code pulled after last sensor change and got the code for short in RF. I just got tire of it, but I do have a new AC Delco sensor in my storage tubs of goodies.
 
1500 and light duty 2500 trucks have the EGR, VIN "S"

Was the new hub on the RF a quality one? If it isn't in the wiring to the hub sensor, the hub could be getting sloppy and the sensor isn't reading properly.

If the sensor shows an ohm reading it is likely good, I can't remember what the correct reading is.
 
1500 and light duty 2500 trucks have the EGR, VIN "S"

Was the new hub on the RF a quality one? If it isn't in the wiring to the hub sensor, the hub could be getting sloppy and the sensor isn't reading properly.

If the sensor shows an ohm reading it is likely good, I can't remember what the correct reading is.

The sensor did show an Ohm reading and I posted those here. It was low, like 0.15 or something.

The PO had the ABS unplugged when I bought it. I plugged it in and the ABS light came on.

I installed new bearings purchased from MI Bearing, though they were not Timken. ABS worked initially and then progessivley worked spottily until no ABS.

The RF bearing eventually failed due to water intrusion and did so on a road trip vacation. I bought a cheapo from AutoZone and had it installed. The ABS never worked even right after install. It was then that I gave up on it.

I just had the RF wheel off and tested it for play. The upper ball joints have some play in them after 50K miles, but the bearing has no play. I have about 1/8" left on the pads before the feelers kick in.

If I have to replace the bearing with a Timken to get the ABS to work, then I'm going for the the GMT 800 jumbo brake conversion. IMO the greatest single part expense in that conversion are the bearings, then the spindles or knuckles. Easily $400+ for a set of Timken bearings. So if I'm going to change out bearings, I'm going the distance and getting me some jumbo brakes.
 
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1500 and light duty 2500 trucks have the EGR, VIN "S"

Was the new hub on the RF a quality one? If it isn't in the wiring to the hub sensor, the hub could be getting sloppy and the sensor isn't reading properly.

If the sensor shows an ohm reading it is likely good, I can't remember what the correct reading is.
According to official GM VIN decoder there is no "S" version of the 6.5 diesel for 1999 only "F" or "Y" see the link I posted from GM Service.
 
According to official GM VIN decoder there is no "S" version of the 6.5 diesel for 1999 only "F" or "Y" see the link I posted from GM Service.
Thats correct, for 99 there was only the HD F engine. The S light duty smog engine with EGR was for 1500's, and 6 lug 2500 trucks(and somehow a few light duty 8 lug trucks got them). ALL SUBURBANS had F engines without an EGR valve(even 1500's), all tahoes got S engines, all 1500 pickups got S engines if they had a turbo(there was some N/A engines early on), 2500's are about half and half for S VS F engines, and 3500's were all F engines. I don't have any diagrams or such for a 99, only my 95. Cali can be quite confusing trying to figure out which is which. Also I believe once a vehicle is 2 years old, a non Cali vehicle can be brought in, and only has to meet the federal emissions standards, not Cali's(even though many emission test stations have tried telling peopel they have to meet Cali standards once they are brought into Cali).
 
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