128keaton

Hey folks. We just finished dropping the rebuilt 3.0 in (yes, you can piss on me for putting the 3.slow back), and it runs pretty good, aside from a single exhaust leak, and the darn code 52. I took apart the top end in January, replaced the KS and pigtail, went away mostly, came on from time to time with no pattern seemingly. I was looking at fixing it, but then the head gasket blew, and the rest is history. Well, I was hoping a new engine would 'fix' it, but I think something else is wrong electrically. I just rigged the connector better, taped and made sure nothing was shorting. I drove it around the block, and on the last street after a bump, the light came on. There are other oddities, sometimes the speedo drops to zero and back after putting on the blinkers, and if the reverse switch is plugged in, the cab's fuses blow when its put into reverse. What ground could be doing this? Block to firewall? But, we had a ton of issues getting it timed right. TDC on the crank and the dizzy set to zero made it run like a dog. Any tips? Maybe that? I can't remember how its timed now, but it runs fine.

scope103

Cab's fuses? Gee, on mine they're all labelled. Let me guess it's the gauge fuse. The reverse switch is powered by the gauge fuse, and then provides 12v to the reverse lights. There's a short somewhere; I'd personally start by popping out the taillight assemblies to take a look right there.

TDC on the crank and dizzy set to zero is so far advanced it SHOULD run like a dog. What is it set to now? Did you use the jumper correctly? At 16yrs, the annular rubber ring in the harmonic balancer can fail in shear. Which means that it SAYS it's TDC, but it's not. Usually, that ends up WAY off, but if you're currently way off you should check that. If the ring on yours has failed, it will just get worse.

Speedo drops to zero COULD be a failing VSS1 (it's a classic sign), but it sounds like you've got a lot of bad wiring problems. A VSS1 isn't cheap, so you don't want to replace it if that isn't the problem.

A persistent code 52 almost has to be a problem in the wire from the pigtail back to the ECU. It's a shielded wire, so it's no ordinary lamp cord, and if the shield is sufficiently damaged that it no longer shields the signal, code 52 is your fate. I'd start by sorting out your other wiring problems; on your way you might find a big glob of corroded wire. That wouldn't be good to keep.

128keaton

Ok, hmm, good idea. Blowing fuses in reverse started happening after a trip up the mountains, and the speedo was dropping after driving through a bunch of rain on the highway coming back from that trip.

That leads me to believe ground, but we had all of the grounding points off (I believe, one on the driver side to the engine mount, one on the passenger side to the block right by the fuel line, and the one under the starter) and they looked great. Maybe the VSS1 failing is just a coincidence.

If I were to replace the wiring from the KS pigtail back to the ECU, do I need any special wire? I did order some generic connectors off of Amazon to replace that. I was thinking copper wire -> heat shrink -> call it a day.

Also, one more note, I've been dealing with a bad exhaust leak on the driver's side, maybe thats also a contributor (KS can't read since the values are so skewed?).

And yes, formatting

128keaton

ARRRGH! This is pissing me off. Starting to think its a timing issue versus exhaust (extreme clatter?). All of the seals are new, bolts are crazy tight (on both the downpipes and manifold, and crossover.

I tried looking at the KS wire again too, and I redid how I rigged the connector while I wait for the after market connector to arrive. I tested, drove it around, stop and go, for a while. Last street. Hit a bump and BAM CEL comes on. Now it comes on revving after cranking, etc. It did the same thing last time. ARGH! Why! Why! WHY! I drop a new engine in you and you still piss in my face.

I couldn't trace the wires without removing the plenum(not removing that POS today), but the wires coming out of the cover were sheathed and I couldn't break the sheathing.

I made progress on the reverse. I just jumped the two pins and the lights worked, but the switch kept blowing the fuse. I'll go grab a new switch ASAP.

EDIT: reading other threads, I might have a clue to why the CEL comes on like this. I am NOT using an OEM KS. But the dealership told me to get this one (!!!!) from NAPA. Agh. Just the thought of tearing it down again over the weekend kills me.

scope103

Are you sure? Switches fail all the time, but to fail to a short-to-ground is a little tricky. My first guess is that you've mashed a wire somewhere downstream of the switch. You can try just looking, but I'd pull the connector, use your multimeter to figure out which one has 12v, then check the resistance to ground of the OTHER one. I'd even start by pulling both reverse light bulbs, then checking resistance to ground on the 12v side of the connector with the trans NOT in reverse. If that lead is shorted to ground, you'll be much closer to finding the problem.

Plus you will have saved whatever the switch costs.

128keaton

Alright. Sounds good. Waiting for the afternoon heat to dissipate. Also considering going to auto parts store to pickup an S10 KS. Should I not do that?

128keaton

Well. AutoZone alternator comes back to bite me in the rear. The brake and charge lights are flickering on and off while using the brake. Oh may I mention that it was replaced in May...

128keaton

Ok, I think I have the "pattern", not sure what it would indicate (only curious while I'm waiting for parts). If its been driven a while, then RPMs drop, then it comes on. Or driven, parked for less than an hour, and comes on immediately.

EDIT: talking to myself here . I think, before I go extreme, i'm gonna rewire to the ECU with some coax. Thinking it might have some noise in it somewhere and that the coax would be a good replacement