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How to read aldl log?

EGR solenoid shouldn't be allowing vacuum to the valve at anything other than cruise.

Pull the plug and watch the valve or pull the hose and see if vacuum gets through the solenoid.
 
I pulled the plug and that stops vacuum from going through the solenoid. So it seems that the ecm is calling for egr.
 
Check the two wires. Without looking at the manual, I would be surprised if one wire isn't ignition 12V, and the ECM grounds the other when it meets the right criteria. I'd be looking for a short to ground on that one.

Did you follow the troubleshooting flow chart that's in Eagle Marks post? ECM is looking for a vacuum change in the circuit, I'm guessing the IAC counts are showing that the EGR is the vacuum leak. And if it's seeing the vacuum leak constantly, when the ECM DOES trigger the EGR solenoid, manifold vacuum is not changing, so it throws a code.

But I'd follow the flow chart.

Did some research in my '91 book, so it's LIKELY this is correct, but not guaranteed unless you are dealing with a '91.

8500GVW and less use an EGR solenoid. Over that use EVRV.

Under 8500GVWR use a negative backpressure valve.

I don't see anything saying the EGR is ONLY active at cruise. It sounds like anything off-idle COULD have EGR. Basically the first couple of steps are to check that the EGR valve holds vacuum with the engine off, then while holding the vacuum, turn key to run, engine off, vac should hold. Then it says trigger the EGR through the ALDL while holding the vacuum, looking for it to drop.
 
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I thought I had it fixed. i swapped out the egr solenoid and drove it 70 miles yesterday with no ses light. Drove it today and got code 13 after about 20 miles. Then got code 13 about 5 more times today. Pulled the ecm out today to take a look and everything looks okay its a 1227747 reman unit. the mempak is a ACSW 0028. anyone know what those mempak letters and numbers stand for? I think I will go to the junkyard and get several different egr valves, a egr solenoid, map sensor and maybe an ecm with mempak if the price is right. I'm getting tired of working on this thing.
 
dyeager535 is there any way you could tell me what the part number is on your egr? I see you have an 87 also. The one GM sold me is a 17087196
 
ACSW is the Broadcast Code, which you will see as "BCC". It identifies the vehicle that it was installed in, IE 1987 K5 305, w/3.42 gears, CA emissions, manual trans, etc.

I don't drive my '87 much, and when I do I get a light while cruising, so I expect it's got an EGR issue as well. I can't assume it's the right part. I'll check my parts manual though. May need more info on the truck itself, but I'll post up if I get somewhere.

Whats the engine code? LT9? Found it, ACSW is the right PROM, (CA emissions), 5.7l "K", LO5

According to the parts manual, they sold you the right part. At least we know that much. :)

Did you follow the troubleshooting flow chart Eagle Mark linked to?
 
I've checked the ports in the intake as far as i can see they are clear, and I followed through the chart for code 32, I will go through the chart for code 13. I'm going to pull the o2 sensor and get a new one under warranty.
 
So if I'm looking in the junkyard at ecm's what mempak code should I look for that will work in mine but federal emissions instead of california?
 
I'll have to check in the service manual tonight. I don't believe there is anything fundamentally different in the parts used, just the calibration. It's funny, I never thought about it before, but I wonder what kind of MPG or power differences they made with the CA, Fed, and High Altitude calibration?
 
From what I've heard they pulled timing out of the california tune. So I should pick up a few hp and mpg. But I'm wondering if there is something its looking for thats causing problems, I know the parts that are on it right now are the right ones for federal emissions but have no way to verify what part numbers california emissions are supposed to be. They may be the same but who knows. So far today I haven't gotten a light. I left the ecm out all night and put it back in this morning. Let it idle for about 10 minutes and drove to work.
 
From what I've seen, the CA "hard parts" are no different than any other vehicle with that engine (LO5, etc). However, perhaps the LO5 was only offered in CA. I note that there are usually 2 engines (same displacement) made each year, and I'm unsure why. I noticed that the EGR placement/intake was different in the '87's between the two 350's made, but it doesn't tell you why, just shows the parts in different places.
 
I've got another intake I'll have to see if they are the same, from what I remember they are. The motor has been rebuilt so any internal differences are probably gone.
 
With the parts manual I could easily check the heads/piston part numbers, but that still doesn't really say WHY the engines were different. It very well may have been based on GVWR and reliability.
 
On the way home I got code 32 several times. It seem so random, why has the code 13 gone? I'm wondering if there is something wrong with the ecm?
 
If you are getting the same codes, consistently, it's doubtful it's the ECM. Poor connection somewhere I could buy, BTDT.
 
Depending on price of the ecm at the junkyard, if its too expensive, I'll just try to find a acsu prom. Maybe its the california emissions causing these problems. Its just wierd cause it throws code 13 sometimes then throws code 32 others. Then I can drive it and it throws no codes. If I do find an ecm and prom I will get the egr valve too.
 
michael0584 said:
Depending on price of the ecm at the junkyard, if its too expensive, I'll just try to find a acsu prom. Maybe its the california emissions causing these problems. Its just wierd cause it throws code 13 sometimes then throws code 32 others. Then I can drive it and it throws no codes. If I do find an ecm and prom I will get the egr valve too.
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Save yourself some money. None of the parts seem to be your problem, and your PROM calibration is fine for the hard parts, so there isn't going to be any "conflict" between the two, assuming the hard parts are indeed right, and I think we've established that.
If you want to do something, pull your glove box out, and pull your ECM. Pull the ECM connectors, and inspect each wire terminal to make sure one or two don't move further than the other, since they are locked into the connector. Inspect the pins on the ECM for corrosion. Pop the small metal plate off the top, and remove the PROM assembly, check for corrosion, and reseat.
We've ensured there is no vacuum leak on the motor, anywhere?
 
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