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Aftermath from the Track Friday....(&track pics)

2757 Views 41 Replies 14 Participants Last post by  G--
So CTS2NV and i went out to the track Friday. My engine power reduced light came on halfway through the day. I reflashed the standard magnuson tune and tried a new magnavolt, still didnt work. StealthV suggested i try swapping out the throttle body, which worked for the power reduced mode but something is still wrong.
Last night i was driving and could feel some sputtering. I parked the car at a bar, then within a minute decided to go to another bar. When i got back in the car it wouldnt start. After several tries it all of the sudden did start and ran fine. I decided i was taking it home and swapping cars with the girlfriend. On the way home it died, then started but idled at like 300rpm (barley alive), then ran fine again. Anyone know what i could have hurt? I was driving it pretty hard and have a maggie. CTS2NV stated he used 3rd and 4th gear a lot, i was using 2nd and 3rd almost all day and only used 4th on 1 straight so my rpm's were pretty high. Thanks for all suggestions!

I'll post video tonight, CTS2NV had a minor off track experience on camera, so i had to throw in a NEMSIS laugh!!!

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Great stuff!(on the track, anyway)

I hate to say it, but you're making me glad I don't have a Maggie...
I'll be in the area early tomorrow let me kno if you need me to swing by.
Yea i forget what a "stock" LS6 looks like, so i'm sure ill be looking for the homes of several hoses/wires. I think the only part ill have to buy is the evap hose. The maggie seems fine, but while i have the car in the shop I'm sending the maggie into Magnuson to have them get her an inspection and fix those misaligned pulleys. Anyone looking for a used (newly rebuilt) maggie i may have one out there soon. You'll have magnuson's assurance it's in great shape, 2 magnavolts (1 brand new), Vette FRC's, boost and A/F gauges, my ashtray gauge pod, 2.6" 2.8" and 2.9" pulleys, intercooler is only 2 months old and if you're local i'll be happy to assist in the install. Only thing not included would be the little crankpins which prob cost $5. I wouldnt totally blame my problems on maggie as much as my driving style with the maggie, redlining all day.... :thepan: Damn that adrenaline! Anyway the speedshop at the track has convinced me that if i plan to track the car often i'd be better off having them turn my engine into a 403 stroker. What is a stroker? I hear it all the time but dont know what it means.. Im uninstalling maggie with hope that my extended warranty will cover any engine problems. With the time i've spent on the car in the last several months i think i'll be single if i ask for time to reinstall the maggie, i'd rather drop the car off for a week or two and get the 403 done... That + headers and cutouts i would imagine would sound pretty mean!
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408 stroker!!! just means they punch your block out to a biggger bore more displacement = more power.

btw are those just powdercoated black stock rims???
The engine shop said 403 but ive heard people say 408 on here before... Those are CTS2NV's wheels, I should let him answer ya but yea he got the stockers powder coated, look nice!
KM -

Before jumping to conclusions and yanking the maggie, how about a simple compression test, or, if you have EFILive, use the cylinder balance test...just a thought.

Have you noticed any strangeness with your ECT gauge, digital and/or analog? The PCM wants a constant, steady feed of information for the IAT, ECT, etc. Any one of them with a short will create problems similar to your description...ask me how I know.

Huh? :noidea: jk Good suggestion, the ect gauge, is that same as Air/Fuel gauge? I dont have EFI live, i just dont understand why it's acting so inconsistent. Either be messed up or not! Dont tease me! How would i test the sensors? I prob am over reacting. I just need to get a cheap back up car and take my time i think....
If you track your V a lot, a well prepped suspension is going to make you much faster than a car with 100 more hp...
I mean you can stroke it to w/e size they make parts for. If I was going to spend the money/take the time though.....408/427 alllll the way
How long does it take to build an engine? 1 week, 2 weeks? I have no idea. Also will the computer still work? Something i need to try tonight which prob wont make a difference is reprogramming back to stock and then back to maggie tune, but with the radio fuse pulled. The maggie install instructions emphasize pulling a fuse under the back seat before flashing. i forgot to do that. Think that'll make a difference?
Check for a loose harness connector, air leaks at all the joints between the filter and throttlebody (you are running a new, non-belt trashed and taped Maggie tube, right?), leaking/disconnected vacuum lines, etc.

If you don't have a scanner, take the car to someplace like AutoZone to get the diagnostic codes read.

Reflashing the PCM won't do much besides clear the diagnostic codes which can also be done by disconnecting the battery and has less risk of issues.
Yea i have a new tube, only like 2 weeks old. The problem is the engine light isn't even coming on. Maybe thats a good thing. When it died it was flashing at me, but when i started it this morning it started right up and no engine light. Something i really need to check is i noticed the passenger side muffler hanger broke, the rubber piece, well the magnavolt wires are running in the same area, maybe something happened with the wires? Maybe there's a short which would cause the fuel pump to stop briefly and therefore cause hesitation/not starting and then running just fine??? I didnt think the wire than runs from the trunk to the front was long enough, so there's a splice/extension right in that area..
A flashing check engine light means there is a misfire so a fuel supply issue with the Magnavolt causing it run lean is possible. Running with this hypothesis, there could be internal engine issues from being lean and is why the car seems down on power. A compression test would be a good thing.

If the compression and fuel check out, try forcing the throttlebody to relearn.

1. Disconnect the battery's negative terminal.
2. Wait at least 15 seconds.
3. Reconnect negative terminal.
4. Turn the ignition key to ON. Do not start the engine.
5. Leave the ignition in ON for at least three minutes so that the electronic throttle control will cycle and re-learn its home position.
6. Turn the ignition to OFF.
7. Start and run the engine for at least 30 seconds.
Cool, will check the magnavolt wires tonight and get the compression test hopefully tomorrow. If there's internal damage, wouldnt the engine light be on? Funny how it comes on for a loose airbox and not for a cracked block!
Km -

Sounds like Rick has you covered, but here is some clarification.

ECT - Engine Coolant Temperature. I have twice now had these wires damaged coming off the sensor just below spark plug on cylinder #1. You would be surprised how the computer responds - it throws a tissy fit. It also throws about 15 codes and none of the are related. If the wires FAIL completely, then you'll see the code indicating coolant overtemp or something.

The handheld scanner has (I think) the ability to read the codes - you know - the one you're using from Superchips to flash in the magnuson tune?

Edit: I just reread your post above. RUN NEW WIRES to the Magnavolt - quit F'in around. Do you realize how important that part of the maggie install is.

Lean isn't mean - lean is kaboom.

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Loose airbox you can't see.

Cracked block makes a lot of noise and usually spills guts on the ground - pretty hard to miss.

just below spark plug on cylinder #1. You would be surprised how the computer responds - it throws a tissy fit.

I'll be sure to check the wires tonight. You know i just replaced my plugs,,, it's quite possible i hit this wire in the process.... Will certainly check for that. Is it a connector below the 1st cylinder on the driver side? (Confirming that is cylinder 1). I remember disconnecting something but im pretty sure i plugged it back in, maybe not all the way??

I really appreciate everyone's help and suggestions of things to check. They've got me working today, but the second i get home i'm heading straight for the garage!
That is the correct location. You would have to pull the computer (very easy) and check pin #'s 74 and 80 on the blue connector for continuity to be certain. I just cut them and ran a new lead.

Of course, the question begs, where and why did they short out, and are there additional wires in the harness that will be failing too :nono:

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Well i hope its just unplugged, the ETC. Perhaps it came loose during my plug install? As for the magnavolt wires, the ones running from the back i guess could have been damaged when the exhaust hanger broke? Not sure when that happened though. 2nd question is why did my throttle body go bad at the same time? A little combo of problems i suppose...Glad i had an extra one!
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