When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I've had a Fast 92 on the car with LS7 TB in place since 2015 without issue. I then added the A&A P-1 in winter of 2016 and had it tuned and adapted for on EFI Live in 2017. Never once have I had REP pop up. The car was parked over the winter. Then a few weeks ago I tore is apart to do some fixes and upgrades. The battery was out of the car for 2+ weeks. The TB was removed and disassembled with intent of having the housing powder coated. My buddy got a few bigger contracts at work, so I took it back, reassembled it and put it back on the car. I drove it once and got the REP a few days ago. Then again today it popped up and I was able to pull the code. In both instances it only happened when I gave the car about half throttle to pass.
I'm going through the various checks for voltage, connection, etc tonight. Not finding anything out of order just yet. It seems possible I could have reassembled the TB somehow incorrectly. But it is such a simple piece, I consider that likelihood to be low.
Any thoughts given the situational changes listed?
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
check the pins on the throttle body connectors... I went through this a couple of months ago at a half mile event of all places lol... I have no idea how it happened but the tps signal wire pin was opened up quite a bit and it would go into rep in 3rd or 4th gear at wot but under normal conditions ran fine
Good check. All the pins and female connectors look solid still. I thought the two-wire connector appeared as though the wires were bent/pinched a bit off the end of the connector. I'll get a voltmeter on it tomorrow. I drove it a bit tonight. Normal driving is fine. Plugged an obd2 adapter on and watched the throttle input live (I don't have my EFI Live gear with me right now.) It was fine at least up to 80% or so. When I matt it, that is when REP kicks in. Fun and games.
Good check. All the pins and female connectors look solid still. I thought the two-wire connector appeared as though the wires were bent/pinched a bit off the end of the connector. I'll get a voltmeter on it tomorrow. I drove it a bit tonight. Normal driving is fine. Plugged an obd2 adapter on and watched the throttle input live (I don't have my EFI Live gear with me right now.) It was fine at least up to 80% or so. When I matt it, that is when REP kicks in. Fun and games.
When you say you had it tuned and accounted for with the LS7 TB, does that mean you are using the gold bladed unit or the silver one? Maybe try logging desired TP versus actual and see if you're getting any delta between the two. You can make small adjustments without bricking the PCM.
Well, the car had an hp tuner program done when stock with headers and Cai. I later added the fast and gold blade to that combination and never had the fault code on that untouched tune. Then I added the blower and when done tuned in person on efi live it never came up, nor has it since until the past two weeks. It has been the gold blade throughout because the A@A bracket is for a C5 with the P1 and would not clear an ls2 tb actuator on that side. Some people mentioned the direction of the butterfly opening may affect function of the fast intake or sensors, so my logic was go ls7 brass plate tb and flip it. That has worked a charm for at least two years until now.
Maybe it’s simply defective. I’ve seen people fight their TB issues month after month until they finally succumb to the idea that it’s defective. They replace it and the problem is gone. At least you got a cheap one to function properly so it won’t be expensive to replace if you decide to troubleshoot via substitution.
Last edited by BLOWNBLUEZ06@RKT Performance; Jun 28, 2018 at 06:12 PM.
Funny that you mention it. Because I had disassembled the actuator and put it back together prior to this problem beginning, I *DID* go ahead and order another one last night and will have it Friday. Thankfully, this is the less expensive option for throttle bodies in this case.
However, the symptoms seem to mimic the general experience others have had with LS2/3/7 throttle bodies where above 84% signal it throws the code and rep. I will be able to try observing with EFI live over the weekend. For now, just an obd2 unit which showed approximately 80% before the car threw the code last night. Though I had ordered an UltraGauge adapter and that should be in to play with tonight too.
I got the new throttle body in and plugged it into the harness. Viewing on ultragauge with power on/engine off, it goes to the full 97% throttle and no code thrown while the current installed unit throws the code at 80%.
I can only surmise that when re-installing the actuator to the housing, I either damaged something somehow (almost impossible) or the teeth on one of the three gears must be rotated to a position other than neutral to account for correct travel.
I'll swap the new unit in and make sure it works. Later when I have time I can play with the faulty unit and see if gear placement affects this issue at all.
Tested and running fine. One less thing on the list. But the local CT vette club had their show this coming Sunday, so I'm going to spend the 4th with a few beers while I polish the CCWs and put them on for the season so I'm not paranoid of my winter tires going kaput.
Ye Olde P1516
