89 K5 Blazer - codes, J code intake swap, and stuff

[AJMBLAZER]

1 - Pulled out a paper clip and my Chilton's manual...only to discover it says I can't do it like I could on the OBD-I TBI gasser trucks.
So how do you check the codes? CEL light is on near constantly now and I'd like to know the problem.
Where's the plug?
Anybody know where I can get the tool/scanner?

2 - Monday I swapped on a single plane J code intake. I used a guide over on the diesel forum on CK5 and the guy only mentioned one vacuum hose needing to be disconnected for the solenoids on the d-side rear. Glad I bought the pack of vacuum caps as I used three. One capped off the fitting where the hose that went to the EGR led to, the other capped off the fitting near the vacuum pump that led to the solenoids, and then the last capped off the other end down by the solenoids.
Meanwhile there's another hose that goes from the solenoids down to what appears to be a fitting at the rear of the d-side head. Do I need to remove and cap these?
Are the solenoids supposed to stay there or do they get disconnected and pulled off?

3 - I have intermittent glow plug light issues. It used to be pretty random about coming on when I turned the key when cold. However usually if it didn't come on I could bump the engine over once or twice and then the light would come on, the gp's would cycle, and it would start. Then a few weeks ago it dies completely and left me stranded at home. Found the only ACDelco GP controller for my truck in Traverse City and talked the place into delivering it to a residence. After that things were A-OK until Tuesday after work. Did the same thing, light didn't come on until a few bumps with the starter. Yesterday morning it came on first try and then after work did the same thing...took a bump to get it to come on. This morning it worked fine but I'm not holding my breath for it to work perfectly.
Ambient air temps maybe? Engine still has enough heat in it to make the temp think it's warm enough but not start?
Wiring glitch somewhere?
When it died on me two weeks ago I ran through the trouble shooting diagram and it's what led me to the gp controller.

[AJMBLAZER]

:confused:

[DmaxMaverick]

Early OBDI systems won't help you with a problem. You already know about all it will tell you, with the light on.

1. Remove all the EGR crap (since you don't have the correct intake, anyway). Plug all the related lines.

2. Remove the CEL bulb from the IPC. Or put a piece of tape over it. Or ignore it.

3. Don't worry about it. The ONLY thing monitored by the ECM is smog stuff. It's complaining because you screwed with it, poor connection, or something broke.

Intermittent problems are the worst. Your glow plug issue sounds like either a poor connection somewhere, or a bad controller. The controller is relatively cheap, and you'll likely need one sooner or later (in other words, just replace it if you don't find an obvious wire issue).

[AJMBLAZER]

EGR is gone. Dumpstered it on Monday. The three Solenoids are there still and they have harnesses to them but I'm unsure about them. Do I just disconnect them and toss the whole assembly off the manifold including the stand? Seems like these 89-91 6.2L R/V's are a breed unto their own and no one who writes stuff for them is ever talking about these years, only the older ones. Just had a debate with a guy about whether or not my truck has a SES light.
Still curious about the vacuum line going off one of the solenoids and to the back of the d-side head. Cap those too?

The light has always been on...but the previous owner or someone did some IP work and used the J code intake gaskets...but left everything for the EGR hooked up. So yeah...it was a bit of a mishmash in there and the intake was COATED in oil sludge. I think it was actually sucking through the CDR valve instead of the EGR tubes.

The GP controller is a new AC Delco unit that I installed two weeks ago. Worked great until this week. My troubles completely went away before then. Did it again this afternoon after work. I had to get out and play with the thing a bit. Wondering if I have a bad wire in there somewhere.

[DmaxMaverick]

Yeah. Sounds like a bad connection with your GP controller somewhere. Good luck with that one. Time and determination. Another option is to go full manual. Works well, and it only requires the controller in the driver seat.

Plug all the vacuum lines and pull all the EGR stuff. It's just taking up space at this time. You won't make the computer happy, so you'll have to ignore it, one way or another. The only possible drawback might be the TCC (Torque Converter Control). If it's working, no worries. If not, cross that bridge when you come to it. I'm not sure about the 89 models, but it usually isn't an issue.

[AJMBLAZER]

Is there a write up anywhere for doing the manual gp controller on the civy trucks? I know of one for the 24v military trucks but nothing for the civy models.

The TCC works off of vacuum? Does it have to do with one of those solenoids? Transmission was rebuilt late last year when the guy I got it from had it and it shifts pretty nice...if a bit early (32" tires vs 29" stockers).

[DmaxMaverick]

The manual GP control is the same for civi's, only it's all 12V. Switch/button - relay - GP's. Keep it simple. If you need more description, just holler.

The TCC is NOT controlled by vacuum. However, at some point in history, TCC became dependent on ECM input, which may be effected by the absence of smog components. Some faults prevent TCC lockup under specific conditions. This may not be the case with yours, and I only included that in case you suddenly have TCC problems with no explanation. Only a possibility. The TCC lockup is hydraulic, but is controlled by an internal solenoid with external input. My 85 TCC has been bypassed (manual control) for so long, I couldn't tell you how it was supposed to work. I have a push/pull switch on the shift lever to lock/unlock it (like a 2 speed in medium/heavy duties). At any rate, if you've removed all the EGR stuff, you should be able to chuck the ECM all together. It isn't needed for anything else. 1989 gassers were very different, with the onset of EFI. A Diesel PCM wasn't needed until 1994 with the introduction of Diesel EFI. Federal smog 6.5L F engines (8600+ GVWR) for 92-93 didn't need one.