Ses light Heibeck Chip and Secondaries Question

[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? 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 ?

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.

thanks in advance.

sam

[Kevin]

sounds like you may have a vacuum leak

[Torchred96]

I think you are right. Well, in the interest of making this a reliable fix, I'd like to go the elimination of secondaries route when I do the injectors. I've studied the diagrams, and though I think I understand the system enough, it just seems the system is more trouble than anything else. Actuators leaking, not assembled correctly, then the trouble of taking the plenum off every time for a leak. Not to mention the expense of the individual parts, vacuum pump etc. etc. I like the idea to KISS.

Do you know if the chip I have from Mr. Haibeck will allow deleting the system without setting off a code?

thanks
sam

[Kevin]

in order to remove the secondaries you'll need to do quite a bit of work to get everything out....what i plan to do is wire them open and have mark burn me a new chip for $200 to get the car to run on all 16 all the time and wire the power key to be on even if I take it out.

[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!

[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.

[QB93Z]

If you have a misfire or stumble problem you may want to investigate the injectors. If they are original 1991 injectors they should be replaced. When you have the plenum off, measure the resistance of each injector.

BTW, I fixed the "T" in your user ID.

Jim

[Torchred96]

Jim, thanks for you input and fixing my T Those injectors are just going to be replaced. I don't really see the point of checking them if they have that kind of mileage on them. right? I can then forget about them for a good while. Edit: I understand that it's shotgunning the problem, but what I mean is, I don't have any history on the car and I don't want to be thinking every time I hear a stumble that I shuddah when i couldah..

Kevin mentioned that I might be able to remove the broken key, so I gave it a try and succeeded. I don't know why, but it was a plastic flat key with no teeth, only a groove on both sides. So, I guess I now need to find another key. Thank you Kevin!..saved me a couple hundred there from what I see on ebay. OR, will I even need it with the chip...

Paul, thank you for that in depth response:
Okay, when I had the Haibeck chip in, I would get a ses light. I still haven't pulled the codes as I've been doing some odd jobs on the car. e.g. took out the key from the valet switch, fixed antenna and I took out the Haibeck chip with the intention of sending it back to him for a recalibration with the secondaries removed. I put the original prom back in (in the meantime) and now have no ses light...maybe it takes a while to resurface. Still have the stumble and lack of power..I'm assuming that the stumble is the injectors and will tackle that soon.

Can I keep the power key operational with the haibeck chip when the secondary throttle valves are removed or does that chip just bypass it? My thoughts are that in the normal power mode only eight injectors work and in the full power mode, all 16 will work all of the time...Am I off base here? I like that little switch. Makes the car unique-er


I'd like to do this all at once, injectors, porting plenum and IH's and elimination of secondary throttle valves et al and chip. I got the car cheap enough and it was taken care of very well as far as I can tell. I'd like to continue the care, only make it more reliable/powerful in the process.


sorry for the rambling, but this car has me going nuts....in a very good way. Love to talk about it, look at it, fondle it...etc etc. Well, I'm sure I'm preaching to the choir though.

thank you

[Kevin]

taking out the secondary throttle plates requires digging into the runners and removing all of the hardwear in there. if you just wire the arms in the full open position and then get the car tuned for them it's 99% the same thing for 1/4 of the money.

pulling the plenum isn't hard and it's a right of passage. Enjoy

[Torchred96]

Gotcha. I'm gonna do a search for the cost issue. I don't want to be rude and not do my own research..

Thanks...and that is a gorgeous car you have!