Guest TurboSedan Posted November 10, 2005 Report Share Posted November 10, 2005 this car is driving me up the wall i'm slowly starting to think that a grainger valve MBC is not the way to go for this car. the problem is that it cuts out bad, ecspecially while it's trying to spool. i wish i could datalog and know for sure what the problem was, but my guess is that the chip is pulling timing at lower RPM, and my grainger valve MBC is at fault. just this week the problem has been really bad. sometimes it's fine but more often it's not. i don't know if the cooler temperatures are making the problem more noticeable or what. i DO KNOW, however, that lowering the boost helps the problem go away. i turned the grainger valve MBC down 1.5 turns today, and that certainly helped...the car is almost just as fast this way (compared to higher boost when the problem wasn't noticeable). if i turn the boost up though, it feels like the engine is running on watered down gas...cuts out and basically just doesn't want to go. what's funny is that i dyno'd the car with the MBC turned 2 full turns from where it is now. it didn't cut out on the dyno this way. then while at the dyno i turned the MBC up another 1/2 turn and the problem was there...as shown on the resulting dyno graph (HUGE dip in the graph and a big puff of black smoke out the exhaust). i wish i could at least know the boost level, but unfortunately the Autometer boost gauge i was using was hardly accurate. i'm getting sick of this crap. to make the problem go away completely i need to lower the boost down a little more. i want to swap the TGP wastegate solenoid and lines over to my Cutlass (from my TSTE) and try it, BUT the overboost in the chip is at 14.7psi according to Jay(!) no way will that work....well....i haven't tried it yet but my guess is it won't. maybe it will though...at my elevation i would think i could possibly get away with that boost level. also, the problem i am having has more to do with spool-up/low RPM boost than peak boost/higher RPM anyway. i'll just have to try it out. i could also swap the stock memcal over from my TSTE as well, but i've tried that before and the idle was way too low and it was cutting out even worse with that memcal anyway. fwiw my TSTE uses stock TGP 'AUFR' memcal....as does my Cutlass, but obviously the 'AUFR' chip is modified in the Cutlass. exactly how it has been modified is unknown to me, as i don't have an EPROM burner or GMPCM software to directly compare the stock 'AUFR' chip i have in the TSTE to the modified one in the Cutlass. i'm going to mess around with some stuff tomarrow and hopefully narrow the problem down. i tried swapping the MAP sensors over and had the same problems. i even swapped the 727 ECM over and no change. however, the 727 ECM that was in the Cutlass up until a couple days ago had a bent pin which wasn't even plugged in! jeez, i could hardly believe that but regardless, swapping the ECM over didn't make any differences that i could tell. i'm still not sure what that pin was for. moral of the story, i need to get myself a laptop ASAP trying to troubleshoot and/or get more power out of this car without datalogging is ridiculous! well anyways, sorry for the rambling :oops: if anyone has any insight/direction/advice i would appreciate it, unfortunately i can't quite afford a laptop yet Quote Link to comment Share on other sites More sharing options...
Nick1234 Posted November 10, 2005 Report Share Posted November 10, 2005 josh i am/was having the same problem. I ran my fastest time with the screw out on the boost controller ( drilled out the hole in the stock boost controller.) Is it because the car is leaning out? The injects aren't that big? The only problem is i don't have the boost gauge in yet. This was my assumption. Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 10, 2005 Report Share Posted November 10, 2005 depends on what pin it was....you have the adapter with the atmel chip on it that goes onto the stock MEMCAL right? on that anyway some pins are bypasses so no real biggy and you said it no change when you swapped it out. all i can say is you would need to see a datalog and that could tell you whats the problem... Ask Jay to send me a copy of your .bin (if he still has it) and i can look at it and see whats going on, if anything code wise. nope, the memcal i am using uses just uses a modified EPROM....no EEPROM and no adapter. the UV-erase window simply has a piece of black tape over it. another strange thing is that i cannot seem to trigger a code or SES light no matter what i do? if i had to do this project all over again i would have been datalogging from the get-go :oops: i'm gonna PM you soon Dave....i have always been a Mac user and i need help in deciding what kind of PC i will need to get. i have the MaStach ALDL cable, sure wish i could use it Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 10, 2005 Report Share Posted November 10, 2005 josh i am/was having the same problem. I ran my fastest time with the screw out on the boost controller ( drilled out the hole in the stock boost controller.) Is it because the car is leaning out? The injects aren't that big? The only problem is i don't have the boost gauge in yet. This was my assumption. no, definately not leaning out. even with higher boost it was off scale rich - sub 10:1 A/F as seen here: http://www.turbosedan.com/cutlass/dyno1.jpg i am using TGP injectors. Quote Link to comment Share on other sites More sharing options...
Rocketman Posted November 10, 2005 Report Share Posted November 10, 2005 Black puff of smoke? Sounds like you are running too rich (which I doubt) or you arent igniting the fuel properly under boost. Could the extra boost be blowing out your spark? Or it could be the ECM going wacky with the spark timing. Quote Link to comment Share on other sites More sharing options...
Nick1234 Posted November 10, 2005 Report Share Posted November 10, 2005 well let me know what you find out. Sounds like we are having the same problem. Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 10, 2005 Report Share Posted November 10, 2005 at the dyno (and now) the plugs are at .035", so that could very well be a problem. but i don't think the extra boost is blowing the spark out at .035". maybe. this same problem has been around even when the plugs were at .040" and .045" (R42LTS). i gapped them down to .035" because i thought the ignition system might be a little weak. it didn't seem to help. next time i check plugs i am going back to .040". Quote Link to comment Share on other sites More sharing options...
skalor Posted November 10, 2005 Report Share Posted November 10, 2005 Is this a low rpm high throttle angle problem?? I know my car has a problem with compressor surge at high throttle in lower rpms(<3000) in any gear past second. My answer to this was modifying my boost ramp tables so that I can only hit full boost under 100% throttle around 3000 rpms. It kinda sucks that I have to have it that way, but it hits what the wastegate actuator is set at so it's not that bad. I can still spin the tires if I punch it in second...even at 2000 rpms. 8) Quote Link to comment Share on other sites More sharing options...
TurboGTU Posted November 11, 2005 Report Share Posted November 11, 2005 My turbo ford calls for .032-.035 gap. With 12psi and low rpm (under 3K)..you Need to gap the plugs closer..not wider. Try .030 to .032. IF you had the 3100-3400 coils and modual...you might get away with .045-.040. Also..did you check the plugs after the dyno..or now..you might have a Grounded or BAD plug after the incedent. If your not going to use the stock boost controller...use a external vacume selinoid and a TPS swich. The selinoid will keep stock actuator boost..but when the TPS triggers the switch...it will activate the selinoid and send the air to the grinder valve. Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 22, 2005 Report Share Posted November 22, 2005 well i still haven't found the problem. - i checked plugs and they all looked great. i also gapped them back to .040" - pulled the plenum off yesterday and ohm tested the injectors - they all tested 12.5 ohms. - found the MAP sensor plug was messed up BAD. all of the plastic 'tubes' that surround the prongs in the connector were broken! i went to NAPA and bought a new 1-bar MAP sensor connector, and made it fit the 2-bar MAP sensor with a Dremel, then spliced it in (soldered & shrinkwrapped) - also found the CTS was broken to the point that only 2 metal prongs were sticking out of it! the connector was barely even hanging on. got that replaced. - checked all vacuum lines and they all looked fine. after i got the car back together with new plenum gaskets it wanted to idle at 2000 RPM thought i had a vacuum leak somewhere, so i pulled the plenum back off today - didn't find anything wrong. got it back together and it did the same thing so i disconnected the negative terminal on the battery for 5 minutes. now the car idles great. my guess is the old CTS was telling the ECM a bad signal? so i took the car for a spin and it pulled HARD with NO cutting out. then 1/2 hour later i took the car out again with my brother and the cutting out was there again. damn, i didn't fix the problem it is an intermittent problem for sure. i ordered a set of spark plug wires from the dealership and they should be here tomarrow. if that doesn't work i have a spare ICM & coilpacks in my garage i will try out. Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 23, 2005 Report Share Posted November 23, 2005 today i removed my MBC and tried using the TGP wastegate solenoid. the car got wayyyy slower. it felt like it was running minimum boost (4-5psi) that way. really strange considering BFC is 14.7psi in the chip according to Jay. although, the engine didn't cut out at all. so i took the wastegate solenoid back out and reinstalled my MBC. i turned the MBC down a couple turns. that definately helped; the car is alot faster that way compared to using the TGP wastegate solenoid and it doesn't cut out anymore. right now i'm thinking it has to be a weak ignition system that can't fire properly with higher boost levels, OR the ECM is pulling MAD timing for some reason. i still have never gotten any codes yet. just code 12 over and over and i've checked codes lots of times :? new wires go in tomarrow. might be trying my extra ICM & coilpacks too. Quote Link to comment Share on other sites More sharing options...
skalor Posted November 23, 2005 Report Share Posted November 23, 2005 If you are getting more than 2.81* of KR it will command the boost down to what the wastegate actuator is set to. If the computer is only letting the boost control solenoid run what the wastegate actuator is set at then you have a problem. I would scan for KR and also what you're timing advance is to see what's going on. Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted November 26, 2005 Report Share Posted November 26, 2005 i put the new ACDelco wires in today, and that FIXED the problem! after installing the new wires, i slowly turned the MBC up to where it was. it does not cut out one bit anymore, and i would say the car is as fast as ever now i went to WOT enough times tonight to know that the problem is GONE. $55 for the new wire set, but i am happy! thanks for the help guys Quote Link to comment Share on other sites More sharing options...
sl3196 Posted November 26, 2005 Report Share Posted November 26, 2005 8) Quote Link to comment Share on other sites More sharing options...
iTurbo Posted November 26, 2005 Report Share Posted November 26, 2005 I got to drive the turbo Cutlass tonight and it is definately smoother running than ever. Never thought the car would be that fast! You're going to need staged boost control on that car to keep the tires planted in the lower gears 8) Quote Link to comment Share on other sites More sharing options...
god910 Posted November 26, 2005 Report Share Posted November 26, 2005 I got to drive the turbo Cutlass tonight and it is definately smoother running than ever. Never thought the car would be that fast! You're going to need staged boost control on that car to keep the tires planted in the lower gears 8) My car was/is setup on a high low switch. 4 psi launch (W/G spring), and then ECM controll on the high side. I loved it. If you wanna know how it was done shoot me a line. (It's very simple) Quote Link to comment Share on other sites More sharing options...
iTurbo Posted November 26, 2005 Report Share Posted November 26, 2005 I got some solenoids from the junkyard to do it on my Omni. All I need now is a single pole-double throw switch. I plan on having three stages in that car. 1st stage 7-8psi (W/G spring), 2nd stage 14 psi (MBC #1), 3rd stage 18 psi (MBC #2) or higher. I want to rig up some kind of WOT micro switch to keep the boost at the minimal setting unless it's at WOT. As you must know, too much boost at part throttle is not good. Quote Link to comment Share on other sites More sharing options...
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