Autotechnica Posted January 26, 2008 Report Share Posted January 26, 2008 Have you read my RICA thread? I have the same problem. With BCS it limits my boost to 8-10psi. When I use an MBC I get 20psi. Do you have a wideband? I would be very interested to know if we're having the exact same problem. With my wideband, I get 10AFRs when the stock BCS is limiting my boost. With the MBC, I get 11.5 or so afrs. Even with the MBC, I still get those super rich AFRs and it "feels" the same sometimes like it's trying to limit my boost, but can't because of my MBC. If you find out anything, let me know. I'm out of ideas...Bry Link to comment Share on other sites More sharing options...
kildea Posted January 26, 2008 Report Share Posted January 26, 2008 if a car is in limp mode would unplugging the ecu reset it? or same as code reset?different system, but in lh2.4 one must reset the ecu and let it relearn after fixing the last problem, if it goes into limp-home mode it will keep the last best config when you fix it and start driving again, and that'll be the wrong settings.you should reset it and see what happens, doesn't hurt anything and it'll only take a couple of days to retune, besides it's broken anyways and nobody seems to see what's wrong ... what would it hurt to try? Link to comment Share on other sites More sharing options...
TurboTim Posted January 26, 2008 Report Share Posted January 26, 2008 Man has anyone mentioned to check the electrics to it. Just put a test light inline with the boost controller and see if it is working mechanical. This is such an easy problem to fix. If you want PM me and I can figure this out in a second. This is such a simply system. Trust me get my number and I can have this working or at least dianosis it in quickly. Link to comment Share on other sites More sharing options...
Seagrams Posted January 26, 2008 Author Report Share Posted January 26, 2008 Alright, busy day.First fuel cut comes on at like 13-14+ psi, i'm not really sure what it is exactly cause by that time i'm ususally going to fast anyway and watching the road not my gauge, i think thats normal on stock tune.Second, this problem has always been, since i got the car i knew it was losing boost, so over the last year i've been ruling components out, (read the first post in the thread, that'll give you some background).I've reset the ECU (pulled it overnight, put it back, let it learn, Nothing) with 0 change in my problem. No codes, went to my indy today and he noticed my emissions was up so he plugged me up and i passed no problem, (also no DTC's)EDIT: I've been thinking about a wideband, knowing my AFR's would be useful in diagnosing this mystery.This is driving me battier than my ex.I spent most of the day running around getting plastic clips i broke replacing my check valve in the tailgate, which for a simple job took much longer than replacing my window switch. that only took maybe 30 mins and now my window goes down and comes back up (i'm real excited, it blows driving around for a week without being able to open your drivers side window.Still need to unbolt the downpipe from the turbo to rule out the cat, but everyone i've talked to said the cat's not the culprit and nobody's mentioned the EGR so f*ck messing with that yet. I'm gonna crack open on of those BCS. I don't think anyone really knows what exactly is going on in there, so i figured i'd take some pic and help the community, maybe even find something good to clean it out with. And hell maybe that's what's up.Keep em coming guys, we'll show my car whose the boss here....thanks for the help so far.Also, i really really need to put Tom's endlinks on.... I can't freaking wait.... Link to comment Share on other sites More sharing options...
TurboTim Posted January 27, 2008 Report Share Posted January 27, 2008 Again has anyone mentioned to check the electrics to it. Just put a test light inline with the boost controller and see if it is working mechanical. This is such an easy problem to fix. If you want PM me and I can figure this out in a second. This is such a simply system. Trust me get my number and I can have this working or at least dianosis it in quickly. Link to comment Share on other sites More sharing options...
EricF Posted January 27, 2008 Report Share Posted January 27, 2008 Check the wastegate actuator with a handpump? May be worn and need more preload... I forget stock specs, 3.5-4.5 psi or something? If it is opening too quickly then it may be your issue. Link to comment Share on other sites More sharing options...
Seagrams Posted January 27, 2008 Author Report Share Posted January 27, 2008 Again has anyone mentioned to check the electrics to it. Just put a test light inline with the boost controller and see if it is working mechanical. This is such an easy problem to fix. If you want PM me and I can figure this out in a second. This is such a simply system. Trust me get my number and I can have this working or at least dianosis it in quickly.I like where your head's at Turbo Tim, tell me more.... Link to comment Share on other sites More sharing options...
DARKSIDE Posted January 27, 2008 Report Share Posted January 27, 2008 Tim is right...but u still a remap...iirc, the ECU controls the BCS...so you'll forever hit 5-7psi, w/ a stock ECU, and no MBC...test my theory: swap in another 855 ECU w/remap and see what happens...(forgive me if I'm wrong) B) Link to comment Share on other sites More sharing options...
Seagrams Posted January 27, 2008 Author Report Share Posted January 27, 2008 Tim is right...but u still a remap...iirc, the ECU controls the BCS...so you'll forever hit 5-7psi, w/ a stock ECU, and no MBC...test my theory: swap in another 855 ECU w/remap and see what happens...(forgive me if I'm wrong) yea but i have the R program so shouldn't i be hitting the 10.9psi?but hey if someone wants to throw me a remapped ecu i won't argue. there's just nobody around here, otherwise i'da done that in a sec. EDIT: Tim please explain what you're talking about here, the boat left, and i missed the boat. Link to comment Share on other sites More sharing options...
DARKSIDE Posted January 27, 2008 Report Share Posted January 27, 2008 yea but i have the R program so shouldn't i be hitting the 10.9psi?but hey if someone wants to throw me a remapped ecu i won't argue. there's just nobody around here, otherwise i'da done that in a sec. EDIT: Tim please explain what you're talking about here, the boat left, and i missed the boat.I thought the factory setting for your car was around 7-8...I'm probably wrong about that though...so anyway...while we wait on Tim it's either one of two problems:ECU or BCS...imho of course... Link to comment Share on other sites More sharing options...
EricF Posted January 28, 2008 Report Share Posted January 28, 2008 yea but i have the R program so shouldn't i be hitting the 10.9psi?but hey if someone wants to throw me a remapped ecu i won't argue. there's just nobody around here, otherwise i'da done that in a sec. EDIT: Tim please explain what you're talking about here, the boat left, and i missed the boat.The R ECU should give you 10.5, but on my turbo cars I never saw the supposed 9.6, usually more like 7-8. Check the wastegate actuator, might need more preload. Or, just run a boost controller at 10-12 psi or whatever your preference is. The BCS is nice in terms of keeping it stock, but M4.3's boost control is primitive and usually pretty sporadic. Link to comment Share on other sites More sharing options...
TurboTim Posted January 28, 2008 Report Share Posted January 28, 2008 You know the 2 wires that go to the boost solenoid. Just hook a test light up to it and you should see a duty cycle and the light flashing as you boost. You can probably even do this with the car just brake boosting. Then when you find out that doesnt work. I dont think it will. You need to find if the problem is the power side or the ground side. The solenoid is controled on the ground side. The next check you need to do is see if there is power. So take the test light and hook it to a good ground and test both wires for power. 1 wire should have power all the time. If one wire has power we are good there. Next you need to check for the computer grounding the curcuit. Take your test light hook one end to power the other to the wire that doesnt have power. This wire should blink as you brake boost it. If you lost tommarrow you can call me. When I am at my shop I can get you the wiring diagrams. Link to comment Share on other sites More sharing options...
Seagrams Posted January 28, 2008 Author Report Share Posted January 28, 2008 You know the 2 wires that go to the boost solenoid. Just hook a test light up to it and you should see a duty cycle and the light flashing as you boost. You can probably even do this with the car just brake boosting. Then when you find out that doesnt work. I dont think it will. You need to find if the problem is the power side or the ground side. The solenoid is controled on the ground side. The next check you need to do is see if there is power. So take the test light and hook it to a good ground and test both wires for power. 1 wire should have power all the time. If one wire has power we are good there. Next you need to check for the computer grounding the curcuit. Take your test light hook one end to power the other to the wire that doesnt have power. This wire should blink as you brake boost it. If you lost tommarrow you can call me. When I am at my shop I can get you the wiring diagrams.ok i see what you're saying. But seeing as i don't have a test light, couldn't i just use a VOM or circuit tester to essentially get the same result i.e. seeing if there is current flowing through the wires? I suppose looking for a flashing light is easier than reading a digital tester (especially while under boost ) but is there something i'm missing? Link to comment Share on other sites More sharing options...
TurboTim Posted January 28, 2008 Report Share Posted January 28, 2008 I wouldnt use a DVOM because it doenst simulate a load like a bulb does. Look around the house and I am sure you can find something. Link to comment Share on other sites More sharing options...
Fishey Posted January 28, 2008 Report Share Posted January 28, 2008 So what did you do to the intake lately? Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.