EL CAMINO Code 53, where to start to narrow down issue?

[schwim]

Hello, friends!

1987 El Camino with 305/200 4r

When driving, it takes about 15 minutes or so of driving but eventually the Service Engine Soon light will illuminate. When bridging port A and B, I got only one code, that being 53.

Repair Pal says it can either be system voltage too high or Digital EGR valve solenoid 1 error. Voltage at the battery is within acceptable limits when I check it and the EGR valve on the intake was replaced along with fuel pump and a rebuilt carb from Mountain Man last week.

How can I narrow this down without aiming a parts gun at it? Where should I start?

Thanks for your time!

 

[78Delta88]

First disconnect the battery ground for 10 -15 seconds and see if that clears it. Then on next drive see if it comes back. I think 14.7 to 15.3 or more would spike the high volt measurement. If that is the case you need to find the cause. And even though "new"... It could be you have bad solenoid.

 

[schwim]

First disconnect the battery ground for 10 -15 seconds and see if that clears it. Then on next drive see if it comes back. I think 14.7 to 15.3 or more would spike the high volt measurement. If that is the case you need to find the cause. And even though "new"... It could be you have bad solenoid.

Is the EGR valve located on the intake the solenoid in question or is the solenoid located elsewhere? I've never heard of the egr valve being termed a solenoid. Also, repair pal states

Digital EGR valve solenoid 1 error​

On vehicles with three solenoid EGR valves an open or short on the solenoid 1 circuit will set code 53.

Fault Code Description

• 53 - Digital EGR valve solenoid 1 error

Symptoms

• EGR solenoid 1 will not function

Common Problems

• Broken wire to EGR valve
• Faulty EGR valve

but I don't have a wire going to the EGR valve, I've got a vacuum line. I'll do more Googling.

 

[78Delta88]

The solenoid would control the vacuum signal to the EGR. Should be like a little black box with a 2 wire connector and one vac line going in and another vac line going out.

If I remember ... Been a long time... On driver side in front of carburetor.

 

[78Delta88]

Something similar to these...

 

[schwim]

Wow, I can't find an actual available source for GM 1997168. If mine's not working, do I just look for used and hope for the best?

 

[ELCAM]

1984 El Camino Conquista failing first smog check ever

When the solenoid is de energized , it is open and allows vacuum to the EGR valve. When the solenoid is energized, it closes and cuts off vacuum to the EGR valve. The usual manner a EGR solenoid fails is that it loses its ability to close and and shut off EGR operation when energized. This...

gbodyforum.com

 

[78Delta88]

Try this one...

From another forum going back to 2001 to 2002

Help with famous Code 53 on 87 L69

Well, I'm getting the famous Code 53. I did a search on this forum before the software change, and read what I could, but I didn't see a real firm answer to the issue. Can't search now due to software bug. Wondered if anyone has found a sure cure?By the way, I changed the computer out f...

www.montecarloss.com

 

[78Delta88]

Sounds like 87 to 95 was same basic system, but changes in ECM were causing issues.

 

[schwim]

Sounds like 87 to 95 was same basic system, but changes in ECM were causing issues.

That seems to be the opinion of that thread, that the 87 ecm is problematic in regards to 20 minute/code 53 issue.