Just bought an '87 IROC with a new 350 and a bunch of other updates. Runs very rough at startup and smells rich after a few minutes of running (at which point it will finally idle, albeit very poorly) and the previous owner states he thinks it needs adjustment with the items listed above. My local Chevy dealer won't work on it because the engine isn't original, or that's the excuse they're using. I live in Rapid City SD and am in need of someone who can work on these. Anyone know of someone in SD or Wyoming, or even Colorado that's good with this kind of stuff? I have original shop manuals but would only adjust these settings with help. IE anyone know what the timing ahould be set at? Thanks for any help.

 

Base timing was checked with est disconnected? Other goodies ?
what ecm calibration chip is being used? What injectors?

 

"Base timing was checked with est disconnected? Other goodies ?
what ecm calibration chip is being used? What injectors?"

I'll try to find out and reply. Thanks!

 

If you can't get it sorted w/help from here (which, you're in good hands, here), and you want to get it to NE Utah, I can get it handled for you....that's a long trek though!

 

"Tom 400 CFI If you can't get it sorted w/help from here (which, you're in good hands, here), and you want to get it to NE Utah, I can get it handled for you....that's a long trek though!"

I'm not opposed to making a trip to Utah! I'd just make a vaca out of it. Would I have to leave it and return or are you thinking it could be taken care of within a reasonable amount of time...as in a couple days? Also whereabouts in Utah, just so I can look at a map?

 

I'd think it could be handled in a couple days. Could be fun. Meeting folks form the forums has ALWAYS turned out to be a real pleasure.

Park City.

 

Here's what the previous owner told me concerning what "Tuned Performance" asked about:

"I just turned the distributor until it ran ok.I don't know anything about a calibration chip.Factory injectors.It ran just fine until several months ago then started acting like it does now without me changing anything."

With him saying it ran fine until a few months ago, that makes me feel it's just some sensor that has gone bad and now it runs like crap as a result. Thoughts?

 

I'd agree. If he's telling you the truth, then something has gone wrong. It's not giving you a Check Engine Light?

 

He is most definitely telling the truth.

Yes there's a check engine light and I even have a GM check engine light checker. There are no stored codes. It only blinks a, blink pause blink blink, which is 12 and that means nothing stored.

 

Yep, they'll always blink "12" with the key on, engine off. OK. Well, do you have a timing light? Fuel pressure gauge?

 

Timing light yes, fuel pressure gauge no. But I can probably scrounge one up. I'll respond when I get one. Should I check timing in the meantime? Or are there any sensors or whatever that could be checked as well?

 

I'd start with the basics, so yes, check timing in the mean time. Can you verify TDC, before timing check? Do you know how to do that? Often, these old harmonic dampers have slipped the outer ring and the timing is no longer where it should be, so it's good to verify.

 

"I'd start with the basics, so yes, check timing in the mean time. Can you verify TDC, before timing check? Do you know how to do that? Often, these old harmonic dampers have slipped the outer ring and the timing is no longer where it should be, so it's good to verify."

Tom,
No I don't know how step by step, but I suspect there's a good tutorial on this forum somewhere. Since this is a newly built 350, it wouldn't have an old harmonic damper and at the least would have a new one. Not saying it shouldn't be checked first, just that it's not a 37 year old original 305. If you can point me in the direction of a tutorial I'll check it out and see if I can get it done. I REALLY appreciate the help on this! Thank you.

I

 

I think I could find someone in Billing MT area if you want to slum up here. The mechanic shop down the street from my work is very knowledgeable and I have know him for years.

 

You're right that a new damper wouldn't likely have slipped. However, I'd still be wondering if the engine has the right timing mark and corresponding damper. There are a number of ways to confirm TDC....for the purpose of verifying, (IMO, not necessary to get check it to the degree), I'd remove #1 plug, stick a skinny long something in the hole so as to feel the piston as it rises in the bore. I prefer a long, slender screw driver and in fact, just did this Monday to time a Vortec distributor. Anyway, put it in the hole, turn the crank shaft by hand (NOT using the starter!), and you can feel the piston rise w/the long skinny tool. Turn the crank until the piston slows and stops rising, and "feel" that swell point where the piston is at the top. Then, look at your mark on the damper and the timing tab. Are we "there"? Or is the mark "an inch away" -or some large distance such as that?

If you're w/in a few degrees, I'd say the damper and timing tab are proper and then I'd put the spark plug back in and go ahead and check ignition timing. Remember that you need to disconnect the ESC wire to get a good base timing reading.

 

Billings isn't too far. I'll see how much I can get done with help from the forum and contact you if I don't get it figured out. Thanks!

 

"You're right that a new damper wouldn't likely have slipped. However, I'd still be wondering if the engine has the right timing mark and corresponding damper. There are a number of ways to confirm TDC....for the purpose of verifying, (IMO, not necessary to get check it to the degree), I'd remove #1 plug, stick a skinny long something in the hole so as to feel the piston as it rises in the bore. I prefer a long, slender screw driver and in fact, just did this Monday to time a Vortec distributor. Anyway, put it in the hole, turn the crank shaft by hand (NOT using the starter!), and you can feel the piston rise w/the long skinny tool. Turn the crank until the piston slows and stops rising, and "feel" that swell point where the piston is at the top. Then, look at your mark on the damper and the timing tab. Are we "there"? Or is the mark "an inch away" -or some large distance such as that?

If you're w/in a few degrees, I'd say the damper and timing tab are proper and then I'd put the spark plug back in and go ahead and check ignition timing. Remember that you need to disconnect the ESC wire to get a good base timing reading."

Tom, I'll give this a look-see but probably won't be till the weekend. I'll let you know how it goes. Thanks!

 

It's been a bit since I started this but I'm still working the issue so I hope I can get some advice here. Ordered a new TPS as I couldn't get a good voltage reading with the one that was in it. Also bought a different multi-tester because the one I had didn't go down to thousandths. So...installed the new TPS and got it set to .549 and started it up. Instead of not being able to keep it running basically at all, it will now run and idle but it idles at about 1800 then drops down to about 700 where it almost dies but then fairly quickly surges back up to the 1800 mark. Stays there for a few seconds and starts to drop back down to about 700 and repeats this cycle. The only thing I have done so far is replace the TPS. I don't think from the way it's acting that it's a timing issue. Just not sure what to check next with the new symptoms. Any help is appreciated!

 

Vacuum leaks. Fuel pressure. That symptom is indicative of an lean a/f ratio.

 

Ok thanks Tom. I'll see what I can find along the vacuum leak train of thought.