Hot Headers?!`
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
Hot Headers?!`
I've been struggling getting my 85 to run again. It's begun to run hotter, I've done the timing, replaced plugs, wires, rotor and cap, fuel filter and put the fuel pressure at about 42 lbs. I thought the cat blew out and plugged the mufflers so I've pulled them off (replaced the cat which looked gutted but never was). When I let it idle in the garage at night, if I turn off the lights the headers are glowing slightly. Thought it might be a bad injector but it is not just one cylinder as I'd originally thought. I replaced the injectors 2 years ago with rebuilt ones from Cruizin Performance. I'm not a diagnostitian and am wondering what else to check??!!! It's been running poorly but with no codes. When I push it, it sometimes will run like it used to but then throws a code (Missing Cal Pack)? I've not been driving since I noticed the headers "glowing"!!!!
Melting Slicks
Joined: Mar 2008
Posts: 3,022
Likes: 3
From: Chandler Arizona
Exhaust gas temps being too high means it's running lean. I wouldn't be surprised if it's the injectors again. the older design injectors (especially on these cars) aren't very good.
it's got to be timing or fuel, my guess is fuel. ... have you checked the fuel filter, have you checked the actual pressure at the rail with key to the on position?
it's got to be timing or fuel, my guess is fuel. ... have you checked the fuel filter, have you checked the actual pressure at the rail with key to the on position?
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
Exhaust gas temps being too high means it's running lean. I wouldn't be surprised if it's the injectors again. the older design injectors (especially on these cars) aren't very good.
it's got to be timing or fuel, my guess is fuel. ... have you checked the fuel filter, have you checked the actual pressure at the rail with key to the on position?
it's got to be timing or fuel, my guess is fuel. ... have you checked the fuel filter, have you checked the actual pressure at the rail with key to the on position?
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Not sure than headers slightly glowing in the dark is what I would concentrate upon. I'd be much more interested in vacuum gauge readings and what the spark plugs 'read'; also what the fuel trim is doing.
With no unmetered air (vacuum leak downstream from the MAF), and other basic engine (timing, etc.) things in order, I'd reset the ECM by disconnecting power to it, then see if it runs better. The ECM can learn bad things which are best erased. The price is right on that one, too.
With no unmetered air (vacuum leak downstream from the MAF), and other basic engine (timing, etc.) things in order, I'd reset the ECM by disconnecting power to it, then see if it runs better. The ECM can learn bad things which are best erased. The price is right on that one, too.
Le Mans Master
Joined: Feb 1999
Posts: 9,950
Likes: 40
From: South Carolina
St. Jude Donor '03 & '05
You are running lean if headers are glowing. Misfire, crossed spark plug wires (wrong ones on plugs), timing way off. Easy to due if EST wasnt disconnected when setting timing.
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
Yes, when I let it idle while timing with the EST disconnected the headers got bright red! When reconnected they were much fainter. It's set at about 9 degrees advanced. When at 6 it ran really rough.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Le Mans Master
Joined: Feb 1999
Posts: 9,950
Likes: 40
From: South Carolina
St. Jude Donor '03 & '05
Usually its warm and at the correct idle speed which is probably 550-650 rpm.
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
I believe factory is 6*. Is the tune stock though? What was the timing at before you did this? Was it having the same issue then.
My headers don't glow when I set timing but I usually don't take long to do it either. They shouldn't be glowing period when everything is hooked back up. And all the pipes are glowing, not just one or two?
My headers don't glow when I set timing but I usually don't take long to do it either. They shouldn't be glowing period when everything is hooked back up. And all the pipes are glowing, not just one or two?
Melting Slicks
Joined: Jan 2001
Posts: 2,940
Likes: 5
From: Chesapeake VA
An O2 sensor can get "lazy" over time. It will still function, so it will not cause a check engine light or code, but it will send inaccurate information. On my 86' the O2 sensor was sending a constant "lean" signal, so the engine ran super rich all the time.
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
I've got 22# injectors which is what everyone in the past has told me it runs. Engine is not modified. I had it tuned, allegedly, at the garage and it did run better after they timed it but that didn't impact on the glowing headers. They all glow too. I've got a new O2 so I can replace that. It is not throwing any codes but the tailpipes look like it's running rich but the scanner says it's lean, may be the solution! Thanks, I'll let you know.
