2g rev limit/fuel cut

[Overkill54321]

hey there, i have a 2g with a 2.3 stroker, dsm link v3, that i just rebuilt the motor because it was smoking heavily. anyway i start the car and runs and idles fine and it revs no problem. after about 5 seconds it feels like a fuel cut at 1900-2000 rpm. i can turn the car off and start it again immediatly and it will rev fine again but only for around 5 seconds. what are some things i should start checking?

 

[Spoolin92GSX]

A buddy of mine was having a similar issue, his was a leak in the intake pipe between the MAF and turbo. There's the obvious boost leak test, verify settings in your tune, air fuel ratios, etc. Does it do the same thing if you try to drive it or only stopped/free revving? Tried logging to see if all values look about right?

 

[Overkill54321]

it happens driving or free reving, i will get a boost leak tester and visually inspect for leaks, it just seemed wierd that it revs fine for a few seconds before the cut happens. i guess given that the engine was out something loose or off is likely. i doubt its the tune as it was running fine before i rebuilt the engine. is resetting the ecu something i should try?

 

[Spoolin92GSX]

A battery pull couldn't hurt, making sure all sensors are plugged in tight and reading properly and a boost leak test is where I would start.

 

[Overkill54321]

i will try the battery pull right after breaking bad , the car has dsm link v3 on it, will all of those setting stay in the ecu?
will a coolant temp sensor and plug work off an esi if spliced in? i also have one off a 2.5l cirrus.

all i can say is i will never buy someone elses project again.

 

[Spoolin92GSX]

Settings shouldn't go anywhere, coolant sensors are only a few bucks I would just get a new one to be on the safe side.

 

[Overkill54321]

the wire came right out of the plastic connector, i will need to splice in a new pigtail

 

[Spoolin92GSX]

Junkyard! For the pigtail, if it was me

 

[Overkill54321]

can a leak down tester work for a boost leak tester?

 

[Sebba]

can a leak down tester work for a boost leak tester?

Uuuhh, no.

 

[Overkill54321]

snap-on guy came to work and tried to sell me that, said he had never heard of a boost leak tester.

anyway now it also has a misfire, and the problem is much worse when warm.

 

[Sebba]

snap-on guy came to work and tried to sell me that, said he had never heard of a boost leak tester.

anyway now it also has a misfire, and the problem is much worse when warm.

That's because he's a tool vendor, not a mechanic. You can make a boot leak tester for next to nothing.

 

[Overkill54321]

ok boost leak test done, 3 leaks found and fixed, car runs and idles like a champ, as soon as i tried to drive it i get fuel cut at around 2500rpm while idling or driving.
so what is the next step i should take?
could the ecu or fuel pump be a suspect?

 

[grothe3297venge]

ok boost leak test done, 3 leaks found and fixed, car runs and idles like a champ, as soon as i tried to drive it i get fuel cut at around 2500rpm while idling or driving.
so what is the next step i should take?
could the ecu or fuel pump be a suspect?

Do you have an upgraded fuel pump?? Those 550's may be pushing your stock pump. (that's insisting you have a stock pump since its not in your bio)

 

[Overkill54321]

yea i need to update mods sorry.
yes i have a 255lph, and the car ran fine before the rebuild with the same setup

edit: the problem gets worse when the car is warm. fuel cut happens at 2k

 

[grothe3297venge]

Only thing I can think of now is you need to post a log so someone can look at your tune!

 

[Overkill54321]

i will do that tonight thanks

 

[Overkill54321]

OK so update:
Problem is gone, i have a feeling it was a bad ground, it was attached to a painted section of the firewall. also fixed a number of other minor things and tested the MAF to make sure that was good. the car idles and revs good. sorta.

im leaning out and getting fuel cut at 8psi. I have updated my mods list for everyone to see.

I do not have an AFPR yet, do you think installing one might solve my problem?

550cc injectors not big enough for my setup?

Will HKS 264 cams affect idle? its minor but noticeable

heres a little log from dsm link, 3rd gear pull. not much there but it shows before the fuel cut and when it happens
http://www.freefilehosting.net/talon3rdgearpull