troyhyde Posted June 26, 2012 Report Share Posted June 26, 2012 Hey folks, I recently got the 4.4/4.3 conversion for a '95 wagon with 19T. I'm having some issues and thought I'd put out a feeler to see if anybody else was experiencing problems. (This was actually suggested by Robert/Lucky) He's walking me through this situation like a gentleman and the conclusion may be a defective ECU, just thought I'd see if anyone else is experiencing the same weird issues. Initial problem, car wouldn't go into closed loop. LTFT / STFT fuel trims both were pegged at 0. This is an EGR car with the EGR removed and nothing plugged into the extra EGR vac. valve connector above the radiator cowl. I discovered that the car would not go into closed loop under any circumstances until I plugged something into that plug (an old and not-attached-to anything EGR vac. valve). That seemed to "fix" the issue of not going into closed loop. Fuel trims started to adjust as normal after the dummy valve was plugged in. I thought the problem was solved. Unfortunately, now I discovered i'm not getting any activation of the purge valve for the evap system. I discovered this after noticing a lot of gas fumes coming from the canister: while driving, stopped in the driveway, etc.... the canister seemed very fuel saturated so I swapped it with another. I can't seem to get the purge valve to turn on at all so a day later it is getting saturated again. For reference, any 4.3 ECU I put into the car turns on the valve, not a wiring issue.... Robert and myself are both stumped at this point and the ECU is going back to him to check over for defect. Anybody have any similar problems? Hopefully this is just a bad circuit trace on the ECU.... Tune is otherwise great and Robert is a pleasure to deal with....Sorry for the typo in title! Link to comment Share on other sites More sharing options...
JordanW Posted June 27, 2012 Report Share Posted June 27, 2012 Agreed, Lucky is great to work with. I can't say that I've had any issues with LTFT/STFT, however a month or so ago I had asked him about the EVAP operation. I can't seem to get rid of the fuel vapor smell, especially when it is hot outside. I have replaced all the EVAP rubber hoses as well as the rubber return line from the rail. Nonetheless, there is always a faint fuel vapor smell from the canister area. I have not yet replaced the canister. However, with M4.3 I would notice that the purge valve would activate (pulse) when the A/C was on, after going to the M4.4 Green conversion tune, it didn't. I've swapped out two different round Bosch style valves and even tried a known working Peirburg valve. I am going to pick up a noid light this week and take another look at the LTFT/STFT just to see if I am experiencing the same. I'm still very happy with the Green tune and have no other issues, it's awesome. Link to comment Share on other sites More sharing options...
ARD - Lucky Posted June 27, 2012 Report Share Posted June 27, 2012 Keep me posted on what you find, I'm doing some testing in my 850 as well to see if there are any parallels that line up between us! Thanks Link to comment Share on other sites More sharing options...
Oreo931 Posted June 27, 2012 Report Share Posted June 27, 2012 For reference, the purge valve you're referring to is the small black valve near the upper driver's side corner of the radiator that has an electrical connection and 2 vac lines running to it, correct? If so, I've haven't encountered any problems you're describing. I am running a M4.4 ECU and deleted EGR comwpletely on my '95. (96 intake mani, s60R exhaust mani, EGR wiring cut out from wiring harness.) I put a vac nipple on the connection to the piece that used to run to the EGR valve. Link to comment Share on other sites More sharing options...
troyhyde Posted June 27, 2012 Author Report Share Posted June 27, 2012 For reference, the purge valve you're referring to is the small black valve near the upper driver's side corner of the radiator that has an electrical connection and 2 vac lines running to it, correct? If so, I've haven't encountered any problems you're describing. I am running a M4.4 ECU and deleted EGR comwpletely on my '95. (96 intake mani, s60R exhaust mani, EGR wiring cut out from wiring harness.) I put a vac nipple on the connection to the piece that used to run to the EGR valve. Yea, that's the purge valve. Can you hook up an OBD reader with live data capability to your car and see what the fuel trim data values read? Link to comment Share on other sites More sharing options...
Big Will Posted June 27, 2012 Report Share Posted June 27, 2012 Even though you've tried other ECUs, have you tried a different purge valve just to see? Link to comment Share on other sites More sharing options...
Oreo931 Posted June 27, 2012 Report Share Posted June 27, 2012 Yea, that's the purge valve. Can you hook up an OBD reader with live data capability to your car and see what the fuel trim data values read? My OBD reader doesnt read live data I have a bluetooth OBDII connector but I don't know of any free programs I could download to read those numbers. And iPhone doesn't have any good apps for that sort of thing either Edit: I wanted to add, though, my car gets pretty crappy gas mileage. 15-16mpg city and 20-21hwy (and that's driving conservatively). Not sure whether it's related to the problem you're having though. I think I also smell fuel sometimes, but that might be because I'm running catless. Link to comment Share on other sites More sharing options...
troyhyde Posted June 27, 2012 Author Report Share Posted June 27, 2012 My OBD reader doesnt read live data I have a bluetooth OBDII connector but I don't know of any free programs I could download to read those numbers. And iPhone doesn't have any good apps for that sort of thing either Edit: I wanted to add, though, my car gets pretty crappy gas mileage. 15-16mpg city and 20-21hwy (and that's driving conservatively). Not sure whether it's related to the problem you're having though. I think I also smell fuel sometimes, but that might be because I'm running catless. Gonna be hard to determine anything without live data or some fuel trim info. Without any adaptation you are running off the computer map without any "learning" from the O2 sensor feedback loop. The ECU will run exactly the same whether you just plugged it in, or if you've driven 5000 miles. You could probably unplug the O2 sensor and have the same performance, provided the car isn't smart enough to go into limp mode. I drove my car from Austin to New Orleans recently without realizing it never went into closed loop. (just got the ECU and threw it in before a road trip) I started to investigate after it started to smell of raw fuel. I thought I had a leaking injector or fuel rail it was so bad. There was a noticeable fuel smell in the cabin and I was worried about a fire hazard. That's when I hooked up the OBD scanner and noticed that I never went into closed loop, it was related to the empty plug for the unused EGR vac. controller (after a lot of hair pulling and investigation). 21mpg seems rather low for highway mileage. I don't seem to get anything below 27mpg or above 30mpg on all the T5's here (according to trip computer). That's conservative highway driving. Link to comment Share on other sites More sharing options...
JordanW Posted June 28, 2012 Report Share Posted June 28, 2012 I recorded some live data during a trip tonight. STFT and LTFT were 0.0, car remained in open loop (or open loop-drive), never went into closed loop. O2 1 and 2 voltages change, usually with the same variation. I disconnected the EVAP purge valve on one leg of the trip, made no difference to the fuel trims and did not set and OBDII code. VOL-FCR did indicate a EFI fault for the purge valve. I see no voltage or continuity at the purge valve idling in park with the A/C off. With the A/C on, voltage is negligible (as in 0.05), however resistance is about 25 ohms. VOL-FCR also shows EFI codes for the missing components (422, 621, 616, 447, 251), though there is never a CEL. I have a M4.4 ECU out of a 98 S70 T5A, I'll drop that in tomorrow and see if that changes things. I'm averaging about 25mpg on highway jaunts at about 75mph; mixed driving is about 21-22mpg. Link to comment Share on other sites More sharing options...
Matty Moo Posted June 28, 2012 Report Share Posted June 28, 2012 I didn't have any issues regarding the purge valve in my Wagon. I had replaced it shortly before I received my 4.4 tune from lucky though. Cant comment on fuel trim, but could get 26ish highway if I drove conservatively. Link to comment Share on other sites More sharing options...
troyhyde Posted June 28, 2012 Author Report Share Posted June 28, 2012 I recorded some live data during a trip tonight. STFT and LTFT were 0.0, car remained in open loop (or open loop-drive), never went into closed loop. O2 1 and 2 voltages change, usually with the same variation. I disconnected the EVAP purge valve on one leg of the trip, made no difference to the fuel trims and did not set and OBDII code. VOL-FCR did indicate a EFI fault for the purge valve. I see no voltage or continuity at the purge valve idling in park with the A/C off. With the A/C on, voltage is negligible (as in 0.05), however resistance is about 25 ohms. VOL-FCR also shows EFI codes for the missing components (422, 621, 616, 447, 251), though there is never a CEL. I have a M4.4 ECU out of a 98 S70 T5A, I'll drop that in tomorrow and see if that changes things. I'm averaging about 25mpg on highway jaunts at about 75mph; mixed driving is about 21-22mpg. Okay, looks like you may have the same problem. Do the following and see what happens: start the car with ARD's 4.4 ECU and plug in the OBD scanner, go to the "clear codes" screen, clear the codes, it doesn't matter if you have codes stored or not, it does a soft reset of the ECU. Do this while the car is running. If you suddenly get fuel trims moving, you have the same issue as I have. If this is the case, please report back. This may in fact be a software problem and not a bad ECU..... I didn't have any issues regarding the purge valve in my Wagon. I had replaced it shortly before I received my 4.4 tune from lucky though. Cant comment on fuel trim, but could get 26ish highway if I drove conservatively. Can you check your fuel trims with an OBD tool? Do you hear your purge valve turning on/off. For clarity, are you running a 4.4 ECU in a 4.3 car? Link to comment Share on other sites More sharing options...
Matty Moo Posted June 28, 2012 Report Share Posted June 28, 2012 Yes, it was a 4.4 in a 4.3 car. I scooped up one of the first ones he did last year. But.... I no longer have the car or tune. So I cant check anything. The only issue I had was the cooling fan running, but he took care of that in short order. Link to comment Share on other sites More sharing options...
troyhyde Posted June 28, 2012 Author Report Share Posted June 28, 2012 VOL-FCR also shows EFI codes for the missing components (422, 621, 616, 447, 251), though there is never a CEL. Any way to know what those components are? Link to comment Share on other sites More sharing options...
JordanW Posted June 28, 2012 Report Share Posted June 28, 2012 Yes, after clearing codes, STFT did infact change, not sure about LTFT as I did not take it for a drive. Link to comment Share on other sites More sharing options...
JordanW Posted June 28, 2012 Report Share Posted June 28, 2012 Those EFI codes relate to the the SAS pump, Baro sensor, outside air temp, fuel tank pressure sensor and the fuel shut valve. Those are items that are normally present in a M4.4 car, but not in the M4.3 car. They are not visable with an OBDII code scanner, only VOL-FCR or the VST, maybe DICE but I do not have DICE. Link to comment Share on other sites More sharing options...
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