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Codes 42, 45, 85 and ticking, rattling sound.


Wags391
11-25-2008, 10:00 AM
1992 S10 Chevy Blazer, 4x4, 4.3L, TBI.

Code 42- Electronic Spark Timing, or fuel cutoff relay circuit.
Code 45- Rich exhaust indication.
Code 85- Electronic control module, or transmission input/output speed sensor.

I have had these codes lately along with a ticking sound coming from the area where the tranny meets the engine. The noise has worsened to a loud rattling when accelerating. The ticking can be heard at parked idle, and is very prominent when in gear and accelerating. The rattling is only when accelerating. The man that recently rebuilt my tranny in May said it could be a loose torque converter bolt. The shop said my oil was very dirty, old looking, and low, so they changed it. That surprises me. I don't think it is the oil. One, I change the oil on a regular basis myself, and the noise hasn't gotten any better. One last symptom is a very rough idle. To the point of the engine shutting down at a light. I've checked the timing and it is set at TDC. What is weird about the timing, is when I was setting it, usually I could turn the distributor one way and it would up the RPMs and vice versa. Turning the dist. either way caused the engine to slow down and just about die.

My main concern are the noises and idle, so if the codes are unrelated then I will deal with them later.

MT-2500
11-25-2008, 12:09 PM
Did you unplug the bypass wire to set base timing?

Wags391
11-25-2008, 12:20 PM
Did you unplug the bypass wire to set base timing?

Yes, I did.

Wags391
11-27-2008, 10:45 AM
I have a theory: I had been doing a lot of work around and with the distributor. If somehow something has happened while working with the dist. and/or the oil pump shaft down to the oil pump. My oil pressure gauge has been fluctuating while driving at a steady speed. It never has done that. Could there be a problem with the distributor, pump shaft, or oil pump causing ticking and rattling?

Wags391
11-28-2008, 02:28 PM
Did some "work" today on the S10. Trying to find exactly where the noises are coming from. Looked closely at the distributor and within the hole where the distributor installs. All that looks good except for the wear on the gears of the distributor. I took off the flywheel cover to check that area. Also good. Did find that the CAT is broken up inside. That could very well be my rattling noise. Could pretty much guarantee it. So for the ticking noise? NAPA told me it could be the exhaust gaskets/donuts ticking. Said they do that when a leak occurs. Received a new code today, 43. That adds to 42 and 45. Would replacing the O2 sensor and the ESC solve those problems, along with replacing the CAT?

Wags391
11-28-2008, 09:03 PM
Took the car for a drive. Ticking and rattling sound has disappeared. Of course, the CAT is still rattling, but for some reason the other noises have gone away. Maybe something was loose that I worked on today. Unfortunately, the car doesn't want to "go" when I press the gas. I've had this problem before, but I can't remember what causes it. Timing? Well, I checked that and it's set where it should be. Could it still be a problem coming from those codes, 42, 43, and 45?

Leeann94astro
11-29-2008, 10:03 AM
Took the car for a drive. Ticking and rattling sound has disappeared. Of course, the CAT is still rattling, but for some reason the other noises have gone away. Maybe something was loose that I worked on today. Unfortunately, the car doesn't want to "go" when I press the gas. I've had this problem before, but I can't remember what causes it. Timing? Well, I checked that and it's set where it should be. Could it still be a problem coming from those codes, 42, 43, and 45?


The cat being plugged could cause your vehicle not to want to go when you press the gas. Start there. If it continues after you've replaced it, then continue your troubleshooting.

Wags391
11-29-2008, 11:52 AM
The problem did begin after I banged on the CAT a bit. I should probably start there before replacing the O2 sensor, eh?

Wags391
12-02-2008, 01:05 PM
The cat being plugged could cause your vehicle not to want to go when you press the gas. Start there. If it continues after you've replaced it, then continue your troubleshooting.

I replaced the CAT and that did not help. Though the comb inside broke in half. Crappy, cheap, CAT. Anyway. I am still getting codes 42, 43, 45. Which part would cause the other one to throw a code? Would a bad o2 cause a ECS code or would a bad ECS cause an o2 code?

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