Ses light Heibeck Chip and Secondaries Question

[Kevin]

the chains should be good to 250k+. if you want to talk about the secondary system off line let me know and I'll pm you my phone number, as I'm doing research on what I want to do with it next year.

[Torchred96]

Kevin that is good news there. I was thinking I was already on borrowed time with the chains. It's hard to tell, but the car doesn't appear to have been beat on, it drives as tight as my 96 did with far fewer miles.

Please do Pm me your number. I will give you a call tomorrow if you don't mind.

Thanks again

sam

[GOLDCYLON]

Originally Posted by torchred96

Okay guys Pardon the newb questions. I have searched but not found specific question answered.

I understand that the ses light prevents the secondary throttle valves from opening....or does it?

Yes that is correct

Originally Posted by torchred96

Is that the case even with the H chip installed or does his chip somehow bypass those trouble routines in the computer? I'm pretty sure it's his basic chip described on his page for the 91 lt5. Does that also mean that the secondary injectors are not going to fire as long as there is an ses light ?

im not sure if the key can be bypassed on a 90 model at the PROM level. I think the 90 can be bypassed at the key level only. It can at the PROM level at the 91-95. reguardless of the PROM if the SES lamp is lit the secondaries will not engage

Originally Posted by torchred96

A little history as I understand it from the seller of the car. He told me that he was really unimpressed with the performance of the car and that the power key was broken off in the switch (on or off i dont know). He told me he contacted Marc Haibeck (sorry about the spelling) for a chip. He said that after he put the chip in, he then got an ses light, but the performance was much improved leading him to believe the secondary injectors and throttle valves are opening. I'm pretty sure that the ses light wasn't there before the chip.

I have the paperwork on the chip which says that the default position is full power.

What year is your car?Your profile is not filled out but your refer to a 91 on Hiabecks site?

thanks in advance.

sam[/QUOTE]

[Torchred96]

Ok, took care of my profile. Is there any way to change the t in torchred96 to a capital T? I was kind of in a hurry when I filled it out initially.

The car is a 91, #1581 and born 04/03/91

That's good news, because I'm pretty impressed with the power even with the stumble and the secondaries not opening.

Sorry about the confusion with the Haibeck chip. I bought this car from a dealer in Miami, Fl. He told me he initially planned to keep the car and so purchased a chip after speaking with Mr. Haibech regarding the lack of power and the broken power switch. I think he (the dealer) found that the power switch wasn't the only issue causing the lack of power and decided to unload the car before putting too much money into it.

However, the dealer did tell me that the chip helped a bunch, and that he (dealer) believed that the secondaries were now opening. I had my doubts that they were opening, but then again, it was missing/stumbling too so I thought that could have been the reason for the lack of performance. Mind you, there was no lack of disclosure on the dealer's part, he's was very up-front with me and there were no real surprises...okay, the knock surprised me a bit, But he may not have ever heard it since it doesn't do it all the time.

Do I understand correctly that the codes may be pulled without pulling down the kick panel on the drivers side?

[Kevin]

there's a chance, and I'm not sure this will work, but you maybe able to take the power key switch apart and remove the broken key from it.

[Kevin]

Originally Posted by torchred96

Do I understand correctly that the codes may be pulled without pulling down the kick panel on the drivers side?

yes there's a obd1 port either in or just under the hush panel under the wheel. I'm not exactly sure where it is as i haven't used it in years

[Torchred96]

Hadn't even thought about trying to retrieve the key and attempt to make it useful. Regarding the hush panel, yeah, I misunderstood a reply that said you can get the code right from the dash.

What am I still doing awake..I'm hooked. Got to get up at 4:30!!

Good nite all and thanks for the patience!

[mike100]

Originally Posted by torchred96

Hadn't even thought about trying to retrieve the key and attempt to make it useful. Regarding the hush panel, yeah, I misunderstood a reply that said you can get the code right from the dash.

What am I still doing awake..I'm hooked. Got to get up at 4:30!!

Good nite all and thanks for the patience!

Here's a link...go 1/2 way down the page for the procedure on how to enter diagnostics to get the error codes to display on your speedo display. The other stuff is for earlier years.

http://www.corvettebuyers.com/c4vettes/codes.htm

[mike100]

The ALDL diagnostic plug is down just tucked to the back of the knee bolster where your right knee would be near the console. You'll need a light and a maybe your floormat out on the ground to drop a knee on the street because you'll need to get low to reach it.

[Paul Workman]

Originally Posted by torchred96

ah, I see, all the injectors work together if you have it programmed that way. I think that answers my question.

I really don't plan to reinstall them once removed. I need to do a search on what is required to remove everything completely and the extra work involved. Sounds like taking off the plenum is like opening a can of worms. and all the gremlins of the lt5 seem to be hiding under there. Can't wait to let them all out.

thanks Kevin!

Removing the secondaries completely is NOT a big deal/hard to do. And, you remove an impediment to air flow - prolly not a big deal until the heads are also ported, but adds a bit of incentive for completing the job, IMO.

To remove the throttle rods and bearing, you just place a socket** over the bearing boss and place a fender washer over the socket to make a make-shift bearing/rod puller. Then grease the threads on the throttle rod and screw the throttle rod nut down onto the washer and continue screwing it down and the bearing and rod come out together. (Note: You'll have to remove the air breather box to get to the front throttle bearings/rods, so you'll need a gasket for that air box (Jerry's Gaskets has 'em).

Once the bearings are removed you'll need the Dorman #555-108 plug to fill the hole. I used a little JB Weld on the plugs to provide an abosolute seal before tapping them in using a 3/8" socket as a driver.

All of the vacuum harness, the check valves, the reservoir, actuators, guide plates...alla that comes outta there, leaving only the MAP sensor (under the ECM on a 90, but not sure where on the 91+ MY LT5s) connected. Marc's calibration programs the ECM to turn on the secondaries at above 1% throttle, and to accept atmopheric air pressure as = OK, far as the MAP signal goes.

FWIW, Marc will provide the chip to support the secondary removal, but if asked whether or not he recommends removing the secondaries, he has said many times that unless there is a compelling reason to do otherwise, he does not recommend removing them. Hard to argue with Marc, but considering OBD-I circumstances in IL, I respectfully disagree...and LUV the improved throttle response and the convenience of NEVER having to fuss with all that crap again!! (Besides...if anyone has access to the parts to keep that overly complicated system alive, Marc does. For the rest of us, fixing a secondary problem is a PIA cuz the parts are NOT on some shelf in every ZR-1 driver's garage.)

P.

PS

Might be a good time to remove the bolts from the IHs and put a bit of Blue LockTite on the threads before torquing them down (to 19 ft #). My first "plenum dive" found some of the bolts were little more than finger tight! Use the same LT on the plenum bolts too. Torque the plenum, starting at the center accross and work a little at a time in a spiral circle toward the extemedy bolts. Repete until torque is achieved. As an added precaution, I use a bit of that (nasty) blue Permatex sealer between the IH and the gasket on the IH side only. Before I place the gasket on the IHs, I spray the plenum side of the gasket with silicone lube spray to facilitate easy plenum removal w/o trashing the gasket every time. Don't spray silicone spray down the runners, or you'll run the risk of trahing an 02 sensor...[argh!]

p.