Hey guys, I'm still having idle and throttle response issues and I am still running the auto trans computer since my donor manual computer won't even start the car. What can I do to reflash the eprom to a manual (specifically, like where to get the program and what sort of software and cable) or should I just find another computer? Thank in advance.
Hey guys, I'm still having idle and throttle response issues and I am still running the auto trans computer since my donor manual computer won't even start the car. What can I do to reflash the eprom to a manual (specifically, like where to get the program and what sort of software and cable) or should I just find another computer? Thank in advance.
Hi Derek, I don't think the ECM is really your problem (though that ECM might just be dead). I think there should be some other issue related to your idle / throttle response issues. Do you have a link to where you posted the issues you're having? I can't remember seeing it. Otherwise, can you post them in here?
FYI, I MAY have a spare 84 / 4-Speed ECM and chip. I was just at my storage unit a couple of weeks ago, and had a stack of ECMs that I'd apparently collected. I wrote what each of them were for on the front, so if you have no other options, then I'll look and see if I have one and you can have it for the cost of shipping.
82 T/A I would love to have a 4 speed ecm. I'm not sure why the 86 ecm from my donor car wouldn't even fire the engine but I know 84 was a special year for a lot of little differences from all of the other years. Let me know how you want me to pay for shipping an i'll gladly take it off your hands. I''ve done a full engine rebuild going .030 over bore with aluminum pistons as well as a lightened cam gear. I'm still running the original injector but have a new TPS and AIC valve set to the correct depth. I've reset said IAC as per the book and driven it several miles above the 40 or 45mph threshold. Timing has been set and reset and it still wants to hunt for idle from 300-1500 as well as bucking under acceleration. Any attempt at acceleration from idle to 3k is a struggle. Also, no vacuum leaks detected. I'd like to cross the ecm off of potential culprits. It's my sons car and he's anxious to drive it since he's back from college, can't blame him, I've dragged my feet on this thing for nearly 18 months. lol
82 T/A I would love to have a 4 speed ecm. I'm not sure why the 86 ecm from my donor car wouldn't even fire the engine but I know 84 was a special year for a lot of little differences from all of the other years. Let me know how you want me to pay for shipping an i'll gladly take it off your hands. I''ve done a full engine rebuild going .030 over bore with aluminum pistons as well as a lightened cam gear. I'm still running the original injector but have a new TPS and AIC valve set to the correct depth. I've reset said IAC as per the book and driven it several miles above the 40 or 45mph threshold. Timing has been set and reset and it still wants to hunt for idle from 300-1500 as well as bucking under acceleration. Any attempt at acceleration from idle to 3k is a struggle. Also, no vacuum leaks detected. I'd like to cross the ecm off of potential culprits. It's my sons car and he's anxious to drive it since he's back from college, can't blame him, I've dragged my feet on this thing for nearly 18 months. lol
Easiest thing (because I'm lazy) is you send me an empty box with a shipping label on it! Haha... only problem is, that it's in the storage unit, which is a good 4 hours away. I likely won't be back to the storage unit for a couple of weeks. But I'll double check to make sure I don't have it at home. If I indeed have it, it's yours.
The Fiero ECM's run almost the identical program, except that the auto version provides a signal for the TC lock up and the manual version provides a signal for the shift light. This is as close to plug and play as you can get. The software can be changed in the eprom (chip) but the change wont effect engine operation. As for your problem; it could be the ECM (they can go bad) or a number of other issues, most common would be spark or a vacuum leak. Have you checked for spark and/or a vacuum leak? Could be other things like a clogged fuel filter, low fuel pressure or dirty injector. You will need to do the checks to find the problem but I would focus on spark first.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Yeah, I’ve done all of the things I can think of except for turning the dreaded screw on the side of the throttle body. The engine was fully rebuilt with a .030 bore and aluminum pistons, new vacuum hoses of course, new injector and timing checked and rechecked. Even before the engine rebuild and auto/manual swap, it idled like crap. It has gotten worse though. Aside from sourcing a slightly richer injector from another vehicle, I’m out of options. I’ve also done the IAC valve procedure a few times knowing 84 is alone in many of the seemingly interchangeable parts. Getting a known good ecm from a manual seems like a logical next step to get this thing idling normal. It’s basically undriveable at this point with it’s bucking and slow to no throttle response until I get the revs up to 3k or so. TPS is only about a year old so I have no reason to think this is bad although I may have to revisit it if something doesn’t give up it’s secret soon.
let's rule somethings out. IACV has nothing to do with the system after you start stepping on the gas pedal. so that's out. Idle stop screw doesn't have anything to do with it after you step on the pedal. so that's out.
Take the top of the air filter off and watch the spray coming from the injector. it should look like the water coming from your shower in the bathroom. Even at idle. The throttle body has a pressure regulator built into them. That is what I would check next.
Take the top of the air filter off and watch the spray coming from the injector. it should look like the water coming from your shower in the bathroom. Even at idle. The throttle body has a pressure regulator built into them. That is what I would check next.
The injector has a nice triangle shaped mist spray pattern, no concerns there.
I'm not sure what you think messing with the idle stop screw might accomplish... besides screwing things up even more. I don’t think it will help at all, alas, not touched even though it seems like it should to most.
What is the actual fuel pressure? That’s something I need to do over, I was getting 30-35 when cranking but it never fired up, wasn’t my tester and it needed to go back, so that is a maybe, but fuel pump and filter are new.
What is the ignition timing set to? 8 degrees btdc
Did you have the ALDL jumper in place when you set it? Yes
Are the distributor cap and rotor in good shape? New
Have you checked the resistance of the spark plug leads? Swapped all of them over with the donor car, no change
Have you triple-checked that the spark plug leads are attached to the correct plugs? Yes but I will again
Will the spark jump a full 1/4" gap outside of the combustion chamber? (And no, testing with a 0.060" gap means nothing.) I haven’t tried that, I’ll put it on my list
I’ll get another tester and confirm whats true, but I sill believe the manual ecm would have different idle parameters and throttle response logic, I’ve read in nearly all auto-to-manual swaps the ecm needed to be replaced as well.
But Note that many Test gauge w/ 80 to 100+PSI gauges are not every accurate showing that numbers. 14 maybe ok but definitely not ~ 20 or more even with high range gauge. Most standard gauges aren't very accurate at highest and lowest numbers of whatever numbers on the scale. Is why I found large diameter 0-30PSI gauge and install that in the test set.
High Pressure can cause ECM setting code 45 and can be several things... Iffy regulator pinch return line crap blocking return line
can kill the pump at high pressure too because often reduce fuel flow means can cool or lube right like that, Worse if tank is near empty because no external gas to help cooling.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
When the fuel pressure appears to be 3x more than it's supposed to be, I think that should be the #1 priority to deal with.
Sounds like the wrong pump is installed. .
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Ok, I triple checked the timing and it is spot on 8 degrees, idle is better but throttle response is a bit sluggish with no load but ok. It wants to die when I get the clutch about half out, begins to shutter and shake the whole car. I give it a bunch of throttle but it struggles to move. with the clutch fully engaged it begins to buck and throttle response is nearly nil. It's either wanting to die or needs 4k rpm. Fuel pressure is rechecked with a known good gauge this time and is solid at 12psi with key on, at idle and under no load revving. TPS was rechecked to make sure it is connected properly, no vacuum leaks. I'm basically out of ideas other than a manual cpu installed since this is a auto/manual swap and I still have the auto's computer installed.
At an RPM that allows the engine to run at a relatively constant speed, I'd ground out (not disconnect) one spark plug lead at a time to ensure that each cylinder is playing an equal role in powering the engine. The RPM drop should be similar across the board.
Well great news, the car is running as it should, I honestly don't know what I did to get it sorted. After I connected the fuel pressure gauge it started running better with better throttle response. I took off the gauge and it still ran better as far as throttle response. I drove it without the air cleaner connected and it ran great but I had a check engine light for the map sensor. I put the air filter back on, checked the connections at the map sensor and after driving for a few miles the light went out. It comes on sometimes when reversing but goes off again shortly after. I'm lost but somewhat content for now.
