Fuel Cut on Stock ECU With Boost Controller off

[viperkillertt]

Hey,
I have been having a few issues lately. Well, my Blitz ecu died 3 months ago and after working on my Megasquirt build for 2.5 months, i had to throw in the towel and get a stock ecu so i could drive my car home finally. Well, before i left Spokane I went to the track to have some fun. Well right before I launched i turned my boost controller on. I hadn't tried it since I had put the stock ECU in. It was set to about 14lbs.

Well, anyways, i hit full fuel cut on the track at about 5500 rpmish. I assumed it was simply due to the stock ecu not liking the higher boost and cutting the fuel.

Since then i have not turned on the boost controller. I have been extremely pleased with the performance of the stock ECU and i truly believe it is actually more powerful then the blitz one with a boost controller.

Well, last weekend i was driving between my 2 jobs and i was getting on the freeway like I usually do, petal to the floor. Well, I hit fuel cut. I couldn't believe it. I didn't have time to see where my boost was. Then 2 days later I was getting on an on ramp again and BOOM, once again i hit fuel cut. I always immediately pull my food off the pedal, to not harm anything, but i am so confused. How could i be hitting fuel cut on a stock ECU. Is it possible that my fuel pump is going? I couldn't imagine that after driving the car at 14lbs for a year without any problems.

I havent datalogged it yet to see what the AFR is, I dont really want to push it until i know what is wrong.

Any advice is greatly appreciated. Thanks!

 

[Turbo Drifter]

What else is done to the car? Exhaust?

On my 1jz with BPU mods I would get boost creep over 5000rpm. I installed a JDM 2jz MAP and a Greddy BCC. With the boost controler turned off I would hit 16psi.

As soon as you open the exhaust on the 1jz it really opens it up and boost creep is possible.

Jeremy

 

[tissimo]

cooler weather = boost creep and fuel cut.. its not unusual for 13-14 psi out of the twins with just a 3" exhaust.

 

[viperkillertt]

Ok, i was thinking that was what was going on, but i just wanted to make sure. It feels like when i turn the boost controller. Yeah, i have y pipe, 3" back and big intercooler. So it makes sense, i just haven't ever dealt with it before because i had the blitz. So is it the map or the ecu that is causing the problem? Why would the map be bad?

 

[Evilempire1.3JZ-GTE]

Can you lower your boost to try and avoid it like 12-13psi? you must have an upgraded "Y" & no cat.

With upgrades my car would boost creep 1-2 psi higher then factory also.

 

[viperkillertt]

Can you lower your boost to try and avoid it like 12-13psi? you must have an upgraded "Y" & no cat.

With upgrades my car would boost creep 1-2 psi higher then factory also.

I cannot control it. Stock boost, the controller is off.
I do actually still have the cat. I don't have to, but i believe in the environment. And the dumbshit that made the exhaust welded the cat in, instead of bolting it in, so i cant use my test pipe if i even wanted to. I have been very interested in the difference in power, but i wont know until i rebuild the exhaust and the standalone.

 

[Turbo Drifter]

I cannot control it. Stock boost, the controller is off.
I do actually still have the cat. I don't have to, but i believe in the environment. And the dumbshit that made the exhaust welded the cat in, instead of bolting it in, so i cant use my test pipe if i even wanted to. I have been very interested in the difference in power, but i wont know until i rebuild the exhaust and the standalone.

Dumping the cat will make a very notisable diffrence.

I had a y pipe on my car with a 80mm HKS exhaust and HKS 3 row IC. I would hit 15psi on spool up and at 6500RPM I would be seeing 18psi with the BC turned off.

Jeremy

 

[annoyingrob]

I used to hit 14psi with just a 3" exhaust, y-pipe and intake.
With a set of cams, that dropped to 12psi.

Add in some winter temperatures, and it was 18psi.

 

[viperkillertt]

I used to hit 14psi with just a 3" exhaust, y-pipe and intake.
With a set of cams, that dropped to 12psi.

Add in some winter temperatures, and it was 18psi.

What did you do to stop it? Piggy Back?

 

[annoyingrob]

What did you do to stop it? Piggy Back?

No, even my stock 1JZ was running a full standalone. HKS F-Con V-Pro. I got fed up repairing ECUs.