Chevy 350 help..

-
D

ducter

Well-Known Member
Joined
Aug 4, 2012
Messages
778
Reaction score
24
Location
N.C
Yeah, I know.

Okay, I picked up an 89 k5 with the 5.7 tbi the other day for really cheap. It has a miss that I can't seem to figure out. Truck runs roughly, almost like the plug wires are wrong. It throws a service engine soon and I pulled the code, which was 32. That says egr valve, I replaced it and didn't help so cleaned the OEM one up and reinstalled it, checked the ports and they are blowing and sucking as they should, next I manually pushed the valve and the motor died so I am thinking the egr valve is good.

I changed the plugs, wires, distributor cap and rotor, the old cap and rotor were pretty bad, to the point I thought that was surely the issue yet it remains.

Truck also smells like it's running rich but no smoke or anything. I am pretty stumped at this point and hoping someone has some insight. It really shows up more at cruising speed under light throttle but is evident all the time.

Thanks
 
If I remember They have a idle control motor. They can get gummed up and stick.
If not make sure no vacuum leaks around tbi or intake. GM loves to chew up intake gaskets.
 
Check your vacuum line routing for the EGR valve. I'm a little foggy, but I think they used a control solenoid for the EGR vacuum in those years that may be causing the problem. Also, check the obvious, are the 7 and 5 plug wires crossed? Swap the plugs and maybe do a compression test for giggles.
 
Thanks for the suggestions, I will try and see of any tests can be run on the suggested parts. It does have the ICM, control solinoid and map sensor. I wonder if I shouldn't replaced the pickup for the distributor as well. Just don't have the cash to throw at it less it's going to fix it.
 
The pick up for the distributor either works, or it don't. Its not the problem. I think those engines have the spider injector rail inside the intake. Some times one of the injectors will clogg. If you have to change that, its a ***** to do usually. Try some fuel added injector cleaner and see what happens.
 
My old neighbor had the same problem on his 1988 Camaro with the same EGR code. Turned out it still had the original fuel filter. Changed the filter code went away and she ran great. Just a cheap possibility for you.
 
chryslerfat said:
My old neighbor had the same problem on his 1988 Camaro with the same EGR code. Turned out it still had the original fuel filter. Changed the filter code went away and she ran great. Just a cheap possibility for you.
Click to expand...

^^^this^^^

My son had a similar situation on an old 350 and it was the fuel filter.
 
I'll pull the filter and change it, should be done anyways. Went to start it this morning to move it out of the way and lovely dead battery. Jumped it off and checked the alternator output, it was good so battery must be shot.
 
Frankie said:
Let us know what happens. I'm hoping it's something cheap and easy for ya. :thumbup:
Click to expand...

Will do. I know better then to own a chevy lol, nah, honestly my wife's suburban has close to 200k and out side of the tranny and intake manifold gasket I can't complain. Just needed something cheap to run around in as I am pretty sure job hunting will begin shortly.
 
MOPARMITCH said:
The pick up for the distributor either works, or it don't. Its not the problem. I think those engines have the spider injector rail inside the intake. Some times one of the injectors will clogg. If you have to change that, its a ***** to do usually. Try some fuel added injector cleaner and see what happens.
Click to expand...

The spider injector system is on the Vortec engines, used after '95. The one in the OP's Blazer is a Throttle Body Injection system.
 
If its still showing a EGR code.......its usually not the valve itself, Its the solenoid.
 
MOPARMITCH said:
The pick up for the distributor either works, or it don't. Its not the problem. .
Click to expand...

Sorry, this ain't true

It might be rare, but dist. triggers do develop problems, sometimes due to dist wear, strike damage, or magnetic debri, AKA rust or filings

We even had at least one guy on this board with a Mopar ECU that was triggering erratically, something I did not think would happen.

I would concentrate on one or two cylinders being a problem

Bad plug wire, even a plug, low compression, head gasket.

Run a cylinder balance test by grounding each cylinder. NOTE I said GROUND, do not remove plug wires and let them fire open.

Run a compression / leakdown test
 
Well replaced the fuel filter which was clogged pretty bad but sadly the issue remains. Getting frustrated, but what funs it if it always just works
 
Was going to check the timing, figure it's free to do. Wrong, it walked at some point in time... seems tools I don't use regularly seem to sprout legs. Anyone use the harbor freight timing light? It's cheap, but if it doesn't work well then...
 
Guess it wasn't a built 350. But seriously my 87 V1500 ran rough. I changed the filter and ran some injector cleaner with a tank of fresh gas made a world of difference. Make sure u run all the old gas out then fill up and change the filter. I got lucky I just switched tanks but I don't think the blazers have two fuel tanks.
 
Check the spray pattern of the injectors, one side may be clogged. Also the TBI base gaskets tend to break and leak. Those plastic to rubber vacuum lines are also always subject to failure.

When checking the timing you will need to unhook the brown wire for timing control, could be on the firewall but more likely behind the glove box.
 
Going to get a timing light tomorrow and check that. Still not certain it's not the egr solinoid. Read on a Chevy forum you can disconnect the egr vacuum and plug it, then drive it. I did that but no change.

As for the cats, they are new from the po, he had to have them to pass inspection. Also though, it's more of a jerking miss then a loss of power.
 
Ran a few more test trying to figure it out before spending money. Tested the egr solinoid with my multimeter, ohms was .37 IIRC, getting a good solid 12v to it and when I manually gave it power I heard it click so thinking thats not the issue.
 
Silly question, but did you unhook the battery for a minute after you changed the egr? I'm definitely no expert but I think the computer has to reset itself or it'll keep tossing out the same code as before.

Good luck ...
 
67Dart273 said:
Sorry, this ain't true

It might be rare, but dist. triggers do develop problems, sometimes due to dist wear, strike damage, or magnetic debri, AKA rust or filings

We even had at least one guy on this board with a Mopar ECU that was triggering erratically, something I did not think would happen.

I would concentrate on one or two cylinders being a problem

Bad plug wire, even a plug, low compression, head gasket.

Run a cylinder balance test by grounding each cylinder. NOTE I said GROUND, do not remove plug wires and let them fire open.

Run a compression / leakdown test
Click to expand...

^^^^^^
Pay attention, this is very true. You said the cap and rotor were unhappy, did you look at the pick up and reluctor? I have had rusty reluctors create all sorts of havoc. How are the plugs wires? Did you check for vacuum leaks? Injector spray pattern?

Regardless of who made the engine, basics are basics. Cover them first, then move on.

Take it from the rock who still gets himself spun in a hole from time to time.
 
Just a heads up, I am still getting code 32 but I did put the old egr valve back on thinking it was not the issue, I still have the new one and will put it back on.

I changed the Ignition Control Module and all is well so far. Had the old one tested at oreillys and it failed. Replaced it and truck seems to be running good now, minus the code from the egr valve.

In case any one in the future searches and finds this post, here again were my issues

It is an 89 K5 blazer with a 350 tbi.
Had like a dead miss to it that really showed its head at cruising speeds. Almost as if the motor was shutting off and on quickly.

Things I did were replace plugs, wires, distributor cap, rotor, fuel filter, egr valve and tested the egr solenoid, which was good.

What fixed it was the Ignition Control Module. Might be of help to someone in the future with the same issues.

Thanks for all the help guys. Actually got more here then the chevy forums I tried and hell, one forum http://67-72chevytrucks.com/ still hasnt approved me yet, been 2 damn days.

MoPars and its people rock.
 

Attachments

  • IMG_20131102_135023 (Medium).jpg
    46 KB · Views: 83
You must log in or register to reply here.
-

Back
Top