GOT2B GM Posted September 25, 2007 Report Share Posted September 25, 2007 It seems that for the last few months now, my TGP has been hitting fuel cut more and more often as time progresses. It has not thrown any overboost codes, and now, it seems to want to hit fuel cut at anything much over 7psi. (Autometer boost gauge) I had the OEM injectors ultrasonically cleaned and flow tested a couple months ago, and the fuel pressure checked out OK at the schrader valve. (40 psi) (Not sure about actual FLOW from the pump though) The car is equipped with a KAZ Hot Tune chip. The car used to overboost with my old Jeff M chip, but not as often. All charge piping is secured with T-bolt clamps and new silicone couplers. All vacuum lines to/from the turbo, actuator and solenoid are 6 months old, with clamps or zipties securing them. Plugs, wires, 02 sensor, coolant temp sensor, x-over, knock sensor, K&N cone, wastegate actuator and solenoid, fuel filter, 1.6/1 rockers are 1 year old or less. I've just recently purchased an EP375 fuel pump brand new off of eBay, thinking that my fuel pump may slowly be dying? I have yet to install it. I also have a brand new AC Delco MAP sensor ordered, thinking it may be related. I have a brand new AC Delco O2 sensor waiting to be installed, and am considering dropping the $$$ on a new FPR. What are your opinions? I'd like to hear what you guys think is causing this.... Also! I thought I'd add this in as well. When I'm starting the car when its cold, if it doesn't start on the first crank, I really have let it crank before it'll start. No sputtering, just cranking. Maybe a lack of fuel? I have no fuel leaks. Maybe there's *just enough* pressure there to get it started right away but if not then it needs to prime more to get enough fuel? Either it starts turn-key, or it'll crank for 10 seconds. Mostly turn key though. Hope thats not too confusing. Thanks for the help. Quote Link to comment Share on other sites More sharing options...
Dark Ride Posted September 25, 2007 Report Share Posted September 25, 2007 I'm going to say your fuel pump is on its way out, when I put a brand new fuel in my old LE I had 46 PSI at the rail. Before I changed it is was 38 and causing problems. Quote Link to comment Share on other sites More sharing options...
krenzy Posted September 25, 2007 Report Share Posted September 25, 2007 I'm going to be second in line for the fuel pump suggestion. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 25, 2007 Report Share Posted September 25, 2007 jeff m had this problem once and had to trace down the wire to the source of the problem. it was some shielded wire or something.I vaguely remember him mentioning it but he solved the problem and restored proper timing cut and boost went back to normal. I had that problem too but got the jeff m chip in the other car now and its got a fresh build on it, good cam and everything and its not doing that for some reason. maybe someone else has a better idea of whats going on with that. Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted September 25, 2007 Report Share Posted September 25, 2007 jeff m had this problem once and had to trace down the wire to the source of the problem. it was some shielded wire or something.I vaguely remember him mentioning it but he solved the problem and restored proper timing cut and boost went back to normal. I had that problem too but got the jeff m chip in the other car now and its got a fresh build on it, good cam and everything and its not doing that for some reason. maybe someone else has a better idea of whats going on with that. that would be the CPS wire. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 26, 2007 Author Report Share Posted September 26, 2007 thanks for the replies, so you think it could potentially be a CPS and/or related wiring as well? I just want this thing to boost properly again! Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 26, 2007 Report Share Posted September 26, 2007 I had it do that when the tee on the fpr was dried out. it would only leak around 7 psi or higher. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 26, 2007 Author Report Share Posted September 26, 2007 was it the actual rubber cracking, or was it leaking out the ends? Quote Link to comment Share on other sites More sharing options...
meltboy1 Posted September 26, 2007 Report Share Posted September 26, 2007 why would the CPS affect startup only when the engine is cold?... then again I guess I could ask the same about the fuel pump... I know in my case at least, when the car is warm, it starts on the first crank, but when cold, it takes some time, like it is not getting fuel at all?... Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 26, 2007 Report Share Posted September 26, 2007 If you can pull the tee and it dont stretch before poppin off then it wasnt tight enough. imo the stock tee isnt tight enough. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 26, 2007 Author Report Share Posted September 26, 2007 Hmmm..well I have brand new AC Delco MAP, Crank Position and O2 sensors so I'll install them and go from there, checking vacuum lines along the way. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 27, 2007 Report Share Posted September 27, 2007 if that doesnt fix it ill be surprised. sounds like a plan Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 28, 2007 Author Report Share Posted September 28, 2007 sensors are in. Gonna take her for a spin tomorrow. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 28, 2007 Report Share Posted September 28, 2007 damn that was quick. yea, sometimes it takes a few days of driving around till you find a good opportunity to really stab it a few times and test it out. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 28, 2007 Author Report Share Posted September 28, 2007 Did the "hard to start" routine today. Going for a drive in an hr or so. Still thinking fuel pump, but Kenny thinks it might be ignition.....hmmmmm Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 28, 2007 Report Share Posted September 28, 2007 what kind of plugs and wires? whens the last time the tb was cleaned? Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 29, 2007 Author Report Share Posted September 29, 2007 Well, it still does it. FWIW, my A/F gauge reads full rich when it starts stuttering. Plugs are NGK Iridium TR5IX gapped at 0.040" (8000mi) Wires are Taylor 8mm (12000mi) TB was cleaned after I bought the car (12000mi ago) Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 29, 2007 Report Share Posted September 29, 2007 try some stock plugs at .040 and see if it makes a difference. and a can of tb cleaner and spray it it in there with the throttle open. thats all I can think of for now. when I had the iridiums they did not last long. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 29, 2007 Author Report Share Posted September 29, 2007 Kenny (TGPilot) has suggested R42LTS's (stock) gapped at .028" due to the added boost running his Hot Tune chip. Nobody has R42LTS's in stock so it looks like it's gonna have to wait till Mon or Tues. At least I'm not the only one who made the Iridium mistake. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted September 29, 2007 Report Share Posted September 29, 2007 actually I think the gap was less, I forget. but those are the only ones to get, the r42lts's. I couldnt remember the part # till you said it. oh yea DUH! I meant .035 gap. and maybe less if you got more boost I guess. .028 huh? cool. I was so tired last night when I wrote that. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 29, 2007 Author Report Share Posted September 29, 2007 Found the plugs today, they had them hid behind the counter for some reason. Gonna try and find some time tonight/tomorrow to put them in. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 30, 2007 Author Report Share Posted September 30, 2007 Put the plugs in last night, gapped at .028" and still hesitates/stumbles above 7psi..... Gonna try new wires next I guess. Any suggestions? Quote Link to comment Share on other sites More sharing options...
futuretgper Posted September 30, 2007 Report Share Posted September 30, 2007 your sure your only getting 7psi of boost?? i see your from canada and i would expect your temps have been dipping lower and lower....you sure your not over boosting and hitting cuttoff?? gets colder and colder and it gets easier and easier to overboost = more and more cutoff but if your sure your only getting 7psi then this can be ruled out Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted October 1, 2007 Report Share Posted October 1, 2007 does the cruise work? Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted October 1, 2007 Author Report Share Posted October 1, 2007 yeah, I have an Autometer boost gauge and thats where I'm getting 7 psi from. Yes, the cruise works......?? Quote Link to comment Share on other sites More sharing options...
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