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Discussion Starter · #1 ·
It drove great for a couple hundred miles this year. Then it stalled on a drive to work.

No codes
Has fuel pressure, which flutters while I turn it over
Proper oil level
Proper TPS voltage
Turns over and kinda fires but won't run
Does not matter throttle position

I'm thinking HEI or oil pressure sender.

Thoughts?
 

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Discussion Starter · #2 ·
I unplug the MAF and it starts fine.
Plugged it in while idling and it stayed running.
Got a code 33 somewhere along that route.

MAF byebye?
 

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I unplug the MAF and it starts fine.
Plugged it in while idling and it stayed running.
Got a code 33 somewhere along that route.

MAF byebye?
Code #33: Mass Air Flow Sensor High

found this feedback on another forum, sounds right up your alley. :thumbsup:

Pete Pulos said:
My '85 did the same thing. It turned out to be a bad MAF. An intermittent problem is difficult to diagnose. My car only had about 18K on it when the MAF went. Two things to try. First with the engine running tap on the MAF with the handle of a screw-driver or something else. See if the engine starts to act-up. Second, if this intermittent problem happens again, unplug the connector to the MAF, the computer will then override the input with pre-programmed info. The engine should smooth out when the MAF is unplugged. I ended up buying a new MAF and that cured the problem. The cheapest place for a new Bosch MAF was TPIS for about $180. Good Luck!!!!
 

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Discussion Starter · #4 ·
Getting a Cardone from Orielley Auto tomorrow. $170+tax. Why not? If I still get the 'signal high' crap, I'll buy that inline circuit thingy that only passes the right voltage at the high end.
 

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I'm still a young novice at repairing fuel injection, but I definitely agree with Grumpy about test then replace. (I'd agree with Grumpy on anything actually, he knows his stuff!)

I saved a guy unknown hundreds of dollars before by testing all of his sensors instead of just replacing. Found that there were actually NO bad sensors at all! Did a fuel pressure test and found his injectors to be leaking majorly. All logic pointed to one sensor or the next, or computer issues. If the money isn't an object or concern it still saves time by testing, resulting in more driving time, and we all want that.:thumbsup:

~wd-40:buhbye:
 

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Discussion Starter · #7 ·
It won't run with MAF connected at all. Disconnected it will run. I suppose I could rig a test by starting it unplugged then plugging in and VOM it...

I'll see if I can pierce the connector to get a reading.
 

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Discussion Starter · #8 ·
Turns out it was the MAF. Being the third one I have put in it in 5 years, I got to wondering. So, I looked thru my maintenance and upgrades files and noticed something interesting. The problems started when I openned up the intake some. CAI, K & N, 52mm TB, and ported plenum.

Since I have the old iron heads, the 52mm & plenum work did not really do much other than move the pinch point to the heads. (Headers, punch cat, and Corsas were done previously.)

I took a scope to my bad MAF. Something looked odd. I took a foam swab and what do you know? Burnt crud.

Looking closer at my records, I noticed that I replaced the MAF 2 months after I recharged the K & N.

Seems that K&N are worthless money burning pieces of ****.

Put in a paper filter today. We'll see how long until the MAF farts, again.
 

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I was thinking of getting a K&N filter.I take it you would not recommend it. Any other high flow filters you could suggest?
 

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If you bought the K&N filter contact K&N about it and they may give you a refund. When I worked at Advance Auto Parts the K&N rep. came by and this was one thing people complained about. Most of those A-1 Cardone's are remans and are made in China or Mexico so that maybe your cause. I have a K&N in my Toyota with a MAF and after 60k worth of miles after installing it no problems. Just a thought:thumbsup:
 

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Discussion Starter · #11 ·
I was thinking of getting a K&N filter.I take it you would not recommend it. Any other high flow filters you could suggest?
Don't bother. Our year Vettes could never out perform the paper filters and any rev. Now, if you have some monster engine or some super hi-flo heads and cam... maybe.
 

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Discussion Starter · #12 ·
I am stumped!!! Got a buyer coming in the morning.

Ran great on new MAF. Ran in the rain and spun the tires, then got a MAF low (34).

:WTF

Now it will run poorly when cold, but won't run with MAF connected once warm.

TPS - .54v
IAC set
Timing proper
Reset codes
Plugs are clean
45 psi fuel pressure

Won't run with MAF connected. No codes!

:huh: I'm lost.
 

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Discussion Starter · #13 ·
In limp home mode, it just bucks and stammers and backfires. That doesn't seem right. Idles 'fine', tho...

:huh:
 

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I'm assuming you got the burnt crud from the MAF wires? If so, the K&N was probably overcharged and excess oil got sucked into your MAF, some landed on the heater wire and burned there.

Since you had the thing apart, check for vacuum leaks. Check your connector. Check the wiring.

Unfortunately that's all I have for you as I don't have any experience with anything older than a 99. If you have a service manual, that's where I go.

Hope you get it sorted out quickly, and cheaply.
 

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Discussion Starter · #15 ·
Yeah... I got nothing. This time I got the troubles with the paper filter.
 

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Discussion Starter · #16 ·
Well, it would appear that rubber flashing came off my air cleaner and impacted the MAF hard enough to dent the screen. It then got burgered up and snagged up inside. Methinks it is what caused the f-up.

I try to get pics!
 

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Discussion Starter · #18 ·
You selling the Vette? Do you have a replacement in mind?

Steven
I fully intend to get another Vette. But at the moment, I would rather not have a loan for my wedding, if I can avoid it. Plus, I inherited a '61 caddy with 30k miles that i need to get back on the road!

:thumbsup:

Otherwise, I will be wanting a C6. Just need a buddy to try to get his into my garage. The C4 scraped the dam if i didn't go 1 wheel at a time. Maybe when we get a new house and the winery is taking off?
 
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