Injector driver error '93 ECM - new injectors
05-29-2017, 08:14 AM
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Car: 91 Z28
Engine: 350ci "fastburn 385"
Transmission: T56 / Quartermaster clutch
Axle/Gears: 9", 4.11, Auburn Posi
Injector driver error '93 ECM - new injectors
Hello all,
Not sure if this is the right spot for this question or not--
I have been using TunerPro RT and seeing injector driver "error" flashing every once in a while on either bank, sometimes both. Kinda figured the injectors (original as far as I know) where on the way out, maybe about toast. BLMs would be split while cruising (130 L and 160 R bank). When unplugging the injectors one at a time while idling, it seemed there were several that barely changed the idle. The car also seemed to have a slight "surge" even while cruising (not buck like timing issue). Just a "feeling" that it wasn't making consistent power I guess you'd say.
All this led me down the path of buying Bosch DIII 32 lb/hr rebuilt injectors from FIC. I have them installed, and now the car is terribly lean during warm up – leading me to suspect I had several injectors leaking and richening things up. (I was also only getting about 16.5mpg!) But that’s not the “real” problem. When I took the car out, I now have a major stumble. I thought I had something failing, but I made it home and it didn’t act quite as bad on the way back. Thinking maybe now that the injectors aren’t leaking, any ECM driver problem is now much more noticeable.
And the injector driver error is still there (random pattern, either bank, maybe 1 time every few seconds or so), acting about the same as it did with the stock injectors. What does this error actually mean? Looked in the GM service manual and doesn’t seem to narrow it down that much. When I unplug an injector with it running, the error “pattern” doesn’t seem to change much – I would have thought it would come on solid indicating an injector is missing from the circuit or something. Just leaves me wondering what the error is telling me.
I have checked the harness for ground and +12v. I’ll do the noid light check next to see if I can spot anything odd happening when the error flashes.
I think I read where some guys on the Corvette forums have been able to have the injector drivers actually replaced in the ECM. Anyone know if this is true and who does it? Or will it be easier / cheaper to find another ’93 ECM?
Not sure if this is the right spot for this question or not--
I have been using TunerPro RT and seeing injector driver "error" flashing every once in a while on either bank, sometimes both. Kinda figured the injectors (original as far as I know) where on the way out, maybe about toast. BLMs would be split while cruising (130 L and 160 R bank). When unplugging the injectors one at a time while idling, it seemed there were several that barely changed the idle. The car also seemed to have a slight "surge" even while cruising (not buck like timing issue). Just a "feeling" that it wasn't making consistent power I guess you'd say.
All this led me down the path of buying Bosch DIII 32 lb/hr rebuilt injectors from FIC. I have them installed, and now the car is terribly lean during warm up – leading me to suspect I had several injectors leaking and richening things up. (I was also only getting about 16.5mpg!) But that’s not the “real” problem. When I took the car out, I now have a major stumble. I thought I had something failing, but I made it home and it didn’t act quite as bad on the way back. Thinking maybe now that the injectors aren’t leaking, any ECM driver problem is now much more noticeable.
And the injector driver error is still there (random pattern, either bank, maybe 1 time every few seconds or so), acting about the same as it did with the stock injectors. What does this error actually mean? Looked in the GM service manual and doesn’t seem to narrow it down that much. When I unplug an injector with it running, the error “pattern” doesn’t seem to change much – I would have thought it would come on solid indicating an injector is missing from the circuit or something. Just leaves me wondering what the error is telling me.
I have checked the harness for ground and +12v. I’ll do the noid light check next to see if I can spot anything odd happening when the error flashes.
I think I read where some guys on the Corvette forums have been able to have the injector drivers actually replaced in the ECM. Anyone know if this is true and who does it? Or will it be easier / cheaper to find another ’93 ECM?
05-29-2017, 10:47 AM
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Car: 85 Chevy Caprice
Engine: Small Block 305
Transmission: Auto
Engine won't crank headlights not working
I'm still trying to figure out on posting on a thread on this site. I have a question. I swap my engine 350 out of a 85 chevy caprice and put a small block 305 in. Now nothing is cranking nor is their any power. Can you provide me some suggestions on what may be the problem. Battery is new alternator is new ..
06-04-2017, 01:02 PM
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Car: 91 Z28
Engine: 350ci "fastburn 385"
Transmission: T56 / Quartermaster clutch
Axle/Gears: 9", 4.11, Auburn Posi
Update: injector offsets were the problem!!
Update:
As of yesterday, the car is running much much better. Thank you Steveo on GearheadEFI for the suggestion on the injector offset values. That was the entire problem!! I never would have thought I had bad info. I used the offsets that I posted below (thanks Rbob), and extrapolated as best I could to fill in the other values in the LT1 tune file using an excel generated equation. Also zeroed out the low PW offset table as suggested on Thirdgen.org. (Apparently the Design IIIs actually flow more at low PW so adding PW is the WRONG move there). Having these two tables right has enabled me to continue on with the tune. The low MAP / low RPM areas were still lean, I believe due to the leaky injectors previously adding fuel unknown to the ECM. The car now warms up fine with no surging. Runs better than it ever did, hopefully some sort of fuel mileage will come about as well.
I found a post in Thirdgen.org from member Rbob I believe stating the below:
----------------------------
Here is the PW offset vs. Bat for the 'BB302 injectors:
@44 psi
Value found in thread
6.4 V: 3.01787012
8.0 V: 2.04425964
9.6 V: 1.52886932
11.2 V: 1.20760185
12.8 V: 0.97447267
14.4 V: 0.77577132
15.0 V: 0.74079391*
-----------------------------------
These values are very different that the injector data that I got from FIC. Not sure what the story is there. You can extrapolate the rest of the values using the equation:
y = 62.993x^(-1.638)
Put the volts in as x, and it turns out a value that fits pretty decent.
I do still see the injector driver errors popping up, and the ERROR still shows on injector banks 1 and 2. I'm not sure I feel any effects from that so I'll just keep an eye on it. But she drives like a million bucks.
As of yesterday, the car is running much much better. Thank you Steveo on GearheadEFI for the suggestion on the injector offset values. That was the entire problem!! I never would have thought I had bad info. I used the offsets that I posted below (thanks Rbob), and extrapolated as best I could to fill in the other values in the LT1 tune file using an excel generated equation. Also zeroed out the low PW offset table as suggested on Thirdgen.org. (Apparently the Design IIIs actually flow more at low PW so adding PW is the WRONG move there). Having these two tables right has enabled me to continue on with the tune. The low MAP / low RPM areas were still lean, I believe due to the leaky injectors previously adding fuel unknown to the ECM. The car now warms up fine with no surging. Runs better than it ever did, hopefully some sort of fuel mileage will come about as well.
I found a post in Thirdgen.org from member Rbob I believe stating the below:
----------------------------
Here is the PW offset vs. Bat for the 'BB302 injectors:
@44 psi
Value found in thread
6.4 V: 3.01787012
8.0 V: 2.04425964
9.6 V: 1.52886932
11.2 V: 1.20760185
12.8 V: 0.97447267
14.4 V: 0.77577132
15.0 V: 0.74079391*
-----------------------------------
These values are very different that the injector data that I got from FIC. Not sure what the story is there. You can extrapolate the rest of the values using the equation:
y = 62.993x^(-1.638)
Put the volts in as x, and it turns out a value that fits pretty decent.
I do still see the injector driver errors popping up, and the ERROR still shows on injector banks 1 and 2. I'm not sure I feel any effects from that so I'll just keep an eye on it. But she drives like a million bucks.
