ok, when i replaced my 305 with the 350 i went to tbichips.com, i was on a budget... well i bought the 350 chip, i put it in, and it ran, (where as before it would stutter at idle, and die if i shifted) it idles at like 1400-1500 rpms, advanced about 4* to keep it from backfiring much. when i go wot real fast, as in stomp it, it hesitates, like almost to stall, then picks up. getting like 12 mpg

so i bought a new chip a year later (this week) well, when i put it in, it held an idle at around 600-800 eek. well it stayed running, and it ran PERFECT, absolutely beautiful, double the power, lower rpms at cruise, it was perfect, well 30 minutes later i was waiting for a friend, so i parked, it went back to 600-800 rpms, and then stalled, tried advancing the time, did nothing, stalled.
well, the next day i decided to try and suffer it through work, i work on a marine corps base so i gotta go everywhere at like 20-35 mph, lots of stop signs, lots of lights....
well now in order to stop, i have to hit the brakes and gas, its rough....

so i messed with the timing alot, disconnected and reconnected the battery and static timing...wire thingy appropiately, it stayed the same... idles the same, and then dies.

so i put my old chip back in... but im so sick of it, it costs me about 40$ a week in gas, and it just runs terrible....

can someone tell me what i can check? i went out and looked for the idle speed setting screw, but it was capped by some metal weld or something, is there any way to change that? its going into storage in two weeks, for two months, but i dont want to come back having forgotten everything that was wrong with it...and take another year to try and get this solved... thanks everyone

 

I think you just punch through that cover with somthing narrow and sharp and it prys right out. Its fairly thin.

 

Did you get a 350 knock sensor and ESC module with the swap? What are the specs on the engine: cam, heads, intake? You probably need to do some datalogging.

 

i tried just kinda...whackin it with a screw driver, ill try to use some real tools, i replaced the knock sensor and esc module, i remember that because it was such a pita to get the guys at the auto store to get one for me...questioning me every step of the way. to the extent of my knowledge, its just a 92 l98, i walked into the store and said i want an engine for a 92 chevy, its all stock... datalogging would require me to buy "stuff" to datalog wouldnt it....? im just curiose... were these cars even supposed to run? mine never seems too...

 

With that combo you defintely need more than a caprice cop chip. Do a search on WinALDL its the free program used to datalog. If you have a laptop you can just get a cable to connect and you're on your way.

 

to data log you will need a cable. customefis.com sells for $40. that plus a used laptop will get you started data logging. winaldl is free.

 

is that a dual TBI? if so i would think the idle stop screw can be adjusted but you may need to datalog and set idle in eprom and also check the iac steps. just a thought.

 

I'm sure his VE tables are pretty far off as well as the slope of the timing curve because that's just too different of an engine.

 

the cop car prom is the one that works! im so confused....i guess i need to research this stuff... or just go rip one out of a junker...

 

He still sold you a product.
Obviously it's not working right.
Have him make good on it.

Selling any product means delivering a certain degree of serviciblity. If it don't work, it's his responsibility to make good on his product.

Your a customer, and have rights.
He owns a business, and owes you a decent product.
If he doesn't own an actual business, then he has lots of problems if you push matters.

 

The cop car chip (9C1 Caprice with LO5) works because the 9C1 LO5 was a 350 TBI engine that used the L98 cam..... so the cop car chip, or more specifically the tables used in that chip, is the correct starting chip to use for nearly any modified 350 TBI engine. So that's why it works ok.

I don't know why the aftermarket chips you bought don't work. If someone here scanned them, they could tell you exactly why.

You have headers and an aftermarket exhaust, plus a warm-air open air cleaner. Dunno what you are running for an intake manifold but it's probably the one you had on the 305 (which is not very good btw). So I'd guess you should be making approx 230-235 fwhp if your engine has a cam on-par with the L98, or more like 210-215 hp if you have the non-9C1 LO5 cam (same as the peanut Fcar cam). So you are very marginal with the cop car chip you have, because it's not set up to provide the fuel for the air the engine is pumping. The copcar LO5 chip for 89-90 was intended for a 190 hp 350, and the 91-93 for a 195-205 hp engine, and you're probably above these numbers given your exhaust mods.

You should read the tech pages here on TGO on how to modify your fuel pressure regulator (FPR) so that you can slightly raise the fuel pressure because I'm sure you are running a little too lean. That will help you run better with the copcar chip, but it's a band aid solution. The real solution is having a chip tuned for your engine.... Notice I said tuned, which is different than just buying one.

As far as the chips you bought -- the seller should make good if the product doesn't perform as advertised. You'll have to pursue that yourself. In the meantime, keep the copcar chip in there, read about how to mod your FPR, then do it. Many people merely add a quarter (coin) insoide the FPR as a shim which raise the fuel pressure slightly, although you don't get to have small adjustments. The true FPR mod works better because you can adjust it.

 

The cop car bin leaves alot to be desired in its own right. FWIW my engine runs like pure **** on that calibration compaired to what I have in the '8063. Not enough timing and WAY too rich at low speeds. Not much better then my stock calibration. W/O datalogging all hes doing is jsut taking educated guesses as to what your car needs. Might sound like a broken record by now but the only one who can tune your car right is you, since your the one who has access to it 24/7/365. The only real solution to get it to run well is to burn the proms yourself. I know it sucks when all you want is for the car to run well but thats the only real way to do it since the tbi was never intended to be a high performance system so no calibrations are really set up to run good.

As for the timing, try setting it back to stock or maybe a few degrees ahead and see how it works.

 

dude, you're in New bern? I'd be willing to help screw with timing and fuel pressure if you need to. I live in Greenville, and it's not a bad drive. Let me know, I wouldn't mind for fellow 3rdgen.org guy. Oh, and if you're worried a/b it, I'm not just any jackass mechanic; GM/ASE tech.

 

doh! thanks for the offer dream, if i had read this post a few days ago i would take you up on it, but the cars going into storage for a few months... gotta do marine corps stuff. when i get it back i think ill try just giving it a tune up, and buying all that "stuff" to burn me a chip, thanks guys, and i will talk to the guy, im sure he will compensate me somehow