sfpar Posted May 10, 2007 Share Posted May 10, 2007 Okay, It's been 5 mos. since my car ran and I am really starting to question my decision to upgrade to SDS. Here is the setup: 1978 280z L28eT engine intercooled 60mm throttle body T3/04 turbo 450cc dsm injectors palnet rail sds fuel only 1978 ignition w blaster 2 coil It's all installed but car won't run. SDS recommended installing the autometer tach adapter which I did. Now the car starts for 2 seconds and dies. I have played with different fuel numbers at the lower rpm range and no luck. I have a fuel pressure gauge and it shows 38-40lbs. I even hooked up a seperate 12V batt to the pump just to have it continuously run. What can I say, am I missing anything. Also have 12v to the injector harness while cranking (it does drop to 10v while cranking but comes back to 12V). The SDS guys are stumped. Not good. Thanks. Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 11, 2007 Share Posted May 11, 2007 Okay, It's been 5 mos. since my car ran and I am really starting to question my decision to upgrade to SDS. Here is the setup: 1978 280z L28eT engine intercooled 60mm throttle body T3/04 turbo 450cc dsm injectors palnet rail sds fuel only 1978 ignition w blaster 2 coil It's all installed but car won't run. SDS recommended installing the autometer tach adapter which I did. Now the car starts for 2 seconds and dies. I have played with different fuel numbers at the lower rpm range and no luck. I have a fuel pressure gauge and it shows 38-40lbs. I even hooked up a seperate 12V batt to the pump just to have it continuously run. What can I say, am I missing anything. Also have 12v to the injector harness while cranking (it does drop to 10v while cranking but comes back to 12V). The SDS guys are stumped. Not good. Thanks. First things first - when you say it starts for 2 seconds, how is it running for those two seconds? Is is firing on all cylinders and then it dies, or does it just kind of sputter and then do nothing? Start with the simple stuff - are the fuel injectors injecting fuel into the cylinders? Is it getting spark? Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 11, 2007 Author Share Posted May 11, 2007 First things first - when you say it starts for 2 seconds, how is it running for those two seconds? Is is firing on all cylinders and then it dies, or does it just kind of sputter and then do nothing? Start with the simple stuff - are the fuel injectors injecting fuel into the cylinders? Is it getting spark? It just sort of sputters. I have already pulled a wire while cranking and there is definitely spark. As far as the fuel goes I can't be positive but it sure smells like fuel is going in. I guess I could pull the rail and see if they squirt. Thanks. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 12, 2007 Share Posted May 12, 2007 If you think you have spark and fule then I would go back to check the pully/magnet/hall sensor position, alignment and gap. Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 12, 2007 Share Posted May 12, 2007 if you pull a spark plug, is it wet? Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 13, 2007 Author Share Posted May 13, 2007 If you think you have spark and fule then I would go back to check the pully/magnet/hall sensor position, alignment and gap. Hey Scottie, I chose to do fuel only sds because it would be easier and lessen the chances of me not getting this car going. How funny is that? Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 13, 2007 Author Share Posted May 13, 2007 if you pull a spark plug, is it wet? You know Tim now that you mention it, the plugs seemed rather dry when pulled. I don't think my injectors are allowing enough fuel in. I am going to pull the rail this week and check. Either the signal is not getting to the computer(hence the new tach adapter) or injectors are faulty(highly unlikely. yes they are used but they were completely overhauled by rep. co.). Could a bad ground on the injector wire harness cause this? I will switch ground locations just to see. Thanks. Scott Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 17, 2007 Author Share Posted May 17, 2007 It started today....yippee. It runs like crap but it's a start. It wants to die when I give it any throttle but noticed a major intake leak due to one of the injector o rings failure. Once I get that fixed I'm hoping to be able to tune a bit. Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 24, 2007 Author Share Posted May 24, 2007 Okay, no more intake or fuel leaks and it starts. Here is the problem. It barely runs and when I give it gas it wants to die. The numbers I have dialed in are crazy high (240-250 across the board) and if I try to lean it out, it dies. Talked to SDS and they are saying my injectors are acting like 160cc instead of the 450cc DSM injectors I think I have. I checked the fuel pump and it is running and I am also getting good fuel pressure according to the gauage. Could someone allow me to send pic of my injector and see if maybe it is a lower flowing one (I doubt it). I'm at a loss here and don't know what else to try next. On a side note, I may be comparing apples to oranges here but one thing I noticed is that my old barb style NA injectors seem to have a larger oriface for allowing fuel as opposed to these DSM 450cc injectors. I don't know a lot about injectors and it was just an observation. Also, it may not make much difference but the old injectors, when mounted, go deeper into the manifold than the DSM injectors. I really don't want to buy new injectors but what else can I try. SDS guys are pretty much done with their support. I really need some help on this and if anyone lives or is cruising through the cincinnati area I could use a hand. Thanks. Scott Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 25, 2007 Share Posted May 25, 2007 Okay, no more intake or fuel leaks and it starts. Here is the problem. It barely runs and when I give it gas it wants to die. The numbers I have dialed in are crazy high (240-250 across the board) and if I try to lean it out, it dies. Talked to SDS and they are saying my injectors are acting like 160cc instead of the 450cc DSM injectors I think I have. I checked the fuel pump and it is running and I am also getting good fuel pressure according to the gauage. Could someone allow me to send pic of my injector and see if maybe it is a lower flowing one (I doubt it). I'm at a loss here and don't know what else to try next. On a side note, I may be comparing apples to oranges here but one thing I noticed is that my old barb style NA injectors seem to have a larger oriface for allowing fuel as opposed to these DSM 450cc injectors. I don't know a lot about injectors and it was just an observation. Also, it may not make much difference but the old injectors, when mounted, go deeper into the manifold than the DSM injectors. I really don't want to buy new injectors but what else can I try. SDS guys are pretty much done with their support. I really need some help on this and if anyone lives or is cruising through the cincinnati area I could use a hand. Thanks. Scott I thought I responded to this yesterday, but apparently the post didn't "take"... I did a quick read of the SDS manual online, and have a couple more questions for you. First, what do your MAP FUEL values look like, and what MAP sensor are you using? From what I could tell, the RPM FUEL settings are used to set the VE characteristics of the engine, and then the MAP fuel settings sort of fine tune you to the particular sensor that you are using. If, for instance, you were setup for a 1 bar sensor and were actually using a 3 bar, it appears that you would get pretty much what you are describing here - you'd have to set the RPM FUEL values about 3 times higher than normal, and the more manifold pressure you ran, the farther you'd be off. Quote Link to comment Share on other sites More sharing options...
Clifton Posted May 25, 2007 Share Posted May 25, 2007 Also, are your sure you have dsm 450's? Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 25, 2007 Share Posted May 25, 2007 If you are not sure what injectors you have, then you are off to a bad start with the SDS since the base fuel values are derived from the injector flow rate and cylinder displacement. Make sure you know exactly what injectors you have and the required FP for those specific injectors. Quote Link to comment Share on other sites More sharing options...
Warren Posted May 25, 2007 Share Posted May 25, 2007 I'm thinking injector impedance might not be what you have it set up for, i'e. high or low (resistor pack inline or not). I could be on the wrong track, but I'm thinking it's injector related also. Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 25, 2007 Author Share Posted May 25, 2007 Thanks guys for replying. I can't tell you how frustrating it is to spend 5 mos and all that dough on upgrades only to end up with a large paper weight. First of all, the injectors. I was told these were DSM blue top 450cc's and of course they were advertised as such. They came from a company that refurbs/cleans/flowtests injectors. So, at the suggestion of SDS I then decide to call the folks at witchhunt.com. I read the numbers on the side of the injector to him, which are B450L, and he said "yep, those are 450cc low impedence injectors". Map Values.....the fuel map values available on this system is between 1 and 250. When SDS put my system together they took my 450cc injectors and pre-set it with that in mind. That being said, I should have RPM values around 80. I have it barely running at 250 the max. MAP sensor.....I have the 2 bar MAP sensor. I have not really changed those settings yet because I'm not exactly boosting here. Once again, thanks for your input. This is not an easy fix or if it is, I can't see it. Scott Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 25, 2007 Author Share Posted May 25, 2007 I'm thinking injector impedance might not be what you have it set up for, i'e. high or low (resistor pack inline or not). I could be on the wrong track, but I'm thinking it's injector related also. That is kinda what I was going to track next. COuld it be possible that SDS sent me the injector harness for a High impedence injector? Scott Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 25, 2007 Share Posted May 25, 2007 Map Values.....the fuel map values available on this system is between 1 and 250. When SDS put my system together they took my 450cc injectors and pre-set it with that in mind. That being said, I should have RPM values around 80. I have it barely running at 250 the max. MAP sensor.....I have the 2 bar MAP sensor. I have not really changed those settings yet because I'm not exactly boosting here. Scott Okay - specifically, what are the MAP fuel settings at the following points: -24 0 15 ...and whatever MAP value that corresponds to the place where things crap out. Quote Link to comment Share on other sites More sharing options...
Warren Posted May 25, 2007 Share Posted May 25, 2007 COuld it be possible that SDS sent me the injector harness for a High impedence injector? If you have low impedance injectors, you should have the resistor pack inline... If you told Racetech that you were using low impedance injectors, they should have put it in the harness before sending it to you. I have it barely running at 250 the max. Sounds like you have a MAJOR air leak somewhere, like in the MAP sensor circuit (hoses, not electrical)... Where are you tapping into the intake manifold for the MAP connection? Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 25, 2007 Author Share Posted May 25, 2007 COuld it be possible that SDS sent me the injector harness for a High impedence injector? If you have low impedance injectors, you should NOT have the resistor pack inline... If you told Racetech that you were using low impedance injectors, they should not have put it in the harness before sending it to you. I don't think i have the unit pictured above. I do have in the injector harness a similar type bracket with two diode looking devices on it. If you go to the link http://www.sdsefi.com/specific.html and look at the picture of what comes with the em4 there is a picture of the injector harness there which is what i have installed. I have it barely running at 250 the max. Sounds like you have a MAJOR air leak somewhere, like in the MAP sensor circuit (hoses, not electrical)... Where are you tapping into the intake manifold for the MAP connection? I have it tapped into the fuel pressure reg. vacuum line. I'm pretty sure there are no leaks now. It sounds quiet. Earlier, I had a bad insulator on one of the injectors and it hissed like crazy but it has been resolved. Here is what the Racetech tech replied when I sent him your guys ideas... Good observation on the map sensor. Power up SDS but dont start the engine. Push gauge button and tell me what MP reading is. If it reads close to zero then things are okay. good thinking on your part here. It does read close to zero. Injector imp, not enough to cause this problem, but if you have an ohmmeter then best measure one inj and let me know. I've run low imp setup but actually had high imp injectors in one of my cars, could not tell either.... -B. Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 25, 2007 Author Share Posted May 25, 2007 Okay - specifically, what are the MAP fuel settings at the following points:-24 0 15 ...and whatever MAP value that corresponds to the place where things crap out. It craps out whenever I floor it and will only rev up when gingerly pushing on the accelerator. Map settings are: 25 @ -23 and go to 203 @ 15 psi. -15psi.....47 -05psi.....80 05psi.......133 10psi.......170 15psi.......203 Quote Link to comment Share on other sites More sharing options...
sfpar Posted May 25, 2007 Author Share Posted May 25, 2007 should I try and pick up a set of supra injectors just to try them? I say supra because they are the cheapest on ebay these days that will fit my fuel rail from pallnet. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.