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.
So after last week, I brought back a thread form many years ago, and was told by Admin to make a new thread, well here goes.
1994 LTI motor, So removing the piping appealed to me as Id struggled for a day to remove the pipe bracket on the RHS head, and actually broke it, the idea of having more space to work and the engine bay looking cleaner was a plus,
been stuck at home at the moment, anything I can do with out outlaying big bucks at the moment is the way in heading, until the car runs regular and reliably.
So blank off the exhausts, remove the piping, not sure how to handle the pump at the moment, would like it removed with out having a engine light on.
So went out the hydraulic store and found 2, 22 mm block of bolts, fixed with copper washers should do the trick.Though it a cleaner way than welding them up, as if you want to make it stock no problem. Air pump pipes removed header with block of bolt fitted 22 mm block of bolt with washer
Any ideas on removing the air pump without activating a warning light.
Last edited by C4 1994 Dubai; Apr 16, 2020 at 04:00 PM.
On a 94, you don't yet have OBD2 function testing of the catalytic converters - 96 was the first year for that, and they are the first year to have post-cat O2 sensors. So you won't get that trouble code (DTC). However, if you remove the electric air pump then I believe you would get DTC 29, "Secondary Air Injection Pump Circuit." I can think of two possible ways to avoid that. First, you could figure out the resistance and/or voltage the PCM expects to see on that circuit and try to rig something to simulate it, kind of like a skip-shift eliminator. It would probably just be a resistor in line with a signal. I wonder if anyone else has already figured out what to do? Second, and probably the best option, is to disable it in the PCM tune. I know for a fact that Tunercat has this feature (see pic below). It's not an expensive product and IMO it's well worth having. I don't know what other tuning software is available for 94/95 cars these days, so I can't say if they all allow this to be turned off or not. But that's how I'd do it.
On a 94, you don't yet have OBD2 function testing of the catalytic converters - 96 was the first year for that, and they are the first year to have post-cat O2 sensors. So you won't get that trouble code (DTC). However, if you remove the electric air pump then I believe you would get DTC 29, "Secondary Air Injection Pump Circuit." I can think of two possible ways to avoid that. First, you could figure out the resistance and/or voltage the PCM expects to see on that circuit and try to rig something to simulate it, kind of like a skip-shift eliminator. It would probably just be a resistor in line with a signal. I wonder if anyone else has already figured out what to do? Second, and probably the best option, is to disable it in the PCM tune. I know for a fact that Tunercat has this feature (see pic below). It's not an expensive product and IMO it's well worth having. I don't know what other tuning software is available for 94/95 cars these days, so I can't say if they all allow this to be turned off or not. But that's how I'd do it.
Thanks for the response, my tech guy hope fully has some thing similar or ill be on the hunt for one, unless as you mentioned there's something else out there.
Last edited by C4 1994 Dubai; Apr 18, 2020 at 12:52 PM.
So this is what the manifolds look like now, on the TV cabinet, painted with matt black Rustoleum 2000F paint, well see how it holds up. Sharp castings ground down, hopefully that will help with spark plug installation.The air pipe has been removed and plugged on one side with a bolt and inside with Hylomar Exhaust Putty, to smoothen out the manifold.
On a 94, you don't yet have OBD2 function testing of the catalytic converters - 96 was the first year for that, and they are the first year to have post-cat O2 sensors. So you won't get that trouble code (DTC). However, if you remove the electric air pump then I believe you would get DTC 29, "Secondary Air Injection Pump Circuit." I can think of two possible ways to avoid that. First, you could figure out the resistance and/or voltage the PCM expects to see on that circuit and try to rig something to simulate it, kind of like a skip-shift eliminator. It would probably just be a resistor in line with a signal. I wonder if anyone else has already figured out what to do? Second, and probably the best option, is to disable it in the PCM tune. I know for a fact that Tunercat has this feature (see pic below). It's not an expensive product and IMO it's well worth having. I don't know what other tuning software is available for 94/95 cars these days, so I can't say if they all allow this to be turned off or not. But that's how I'd do it.
There is no longer any need whatsoever to spend money on TunerCats.
TunerPro is free-as-in-beer, and is far more feature-rich thanks to an XDF definition for the $EE (of which 94-95 Corvettes are included). So it can do all the same tuning TunerCats can and way, way more.
For flashing to the car, Fbodytech's Flashhack is superior in every single way to WinFlash/TunerCats. It's lightweight, free, open source, and includes the ability to install a recovery ROM to make the process essentially brick-proof. With WinFlash/TunerCats, if something happens during the flash process, your PCM is a brick. Not so with Flashhack.
So for the cost of just the USB-to-ALDL cable, I'd take that route instead.
Ok thanks for the information, Im not a IT person, looks like someone's going to have to learn, im almost alone over here as not many want to assist with the car, and if they do they want silly money.
There is no longer any need whatsoever to spend money on TunerCats.
TunerPro is free-as-in-beer, and is far more feature-rich thanks to an XDF definition for the $EE (of which 94-95 Corvettes are included). So it can do all the same tuning TunerCats can and way, way more.
For flashing to the car, Fbodytech's Flashhack is superior in every single way to WinFlash/TunerCats. It's lightweight, free, open source, and includes the ability to install a recovery ROM to make the process essentially brick-proof. With WinFlash/TunerCats, if something happens during the flash process, your PCM is a brick. Not so with Flashhack.
So for the cost of just the USB-to-ALDL cable, I'd take that route instead.
I recently saw another post of yours about this (after I posted what you quoted, though). If I still owned my car, I'd definitely be looking into this option.
Ok thanks for the information, Im not a IT person, looks like someone's going to have to learn, im almost alone over here as not many want to assist with the car, and if they do they want silly money.
Honestly the learning curve isn't too bad for doing basic things like disabling features or error codes. Doing tuning yourself will require some education, but if all you want to do is disable emissions devices, it's not bad at all. There are plenty who would be willing to help you through the steps, myself included.
Originally Posted by MatthewMiller
I recently saw another post of yours about this (after I posted what you quoted, though). If I still owned my car, I'd definitely be looking into this option.
Absolutely. As recently as last year WinFlash at least was still a better flash tool for some vehicles. On my dad's '94, for instance, there seems to be an odd communication problem where the ALDL is noisy and so it won't stay connected properly. WinFlash was able to get past the noise and flash successfully several times, whereas the free alternative would have been too risky to try. Now the free alternative not only has a more robust communication routine, but also the aforementioned recovery patch so that even if something were to go wrong, you could pick up where you left off and not end up with a brick (which is what would happen were WinFlash to fail).
Air Pump and piping delete
