RB25 series 2 boost issues

[RBflyer91]

Hey guys. I'm new here and am in need of help ASAP.

I have a 91 s13. 240 that I have swapped an RB25 series to into. The motor is stock the ecu is stock. All of it is stock.

The problem I am having is that I am unable to build full boost. I can floor it and the car will go right at 3 psi according to my gauge. And thats all I can get. It spools fast and runs flawless. But I can't get more then 3 psi. There is no boost controller. I am running wg pressure. I have tried 2 different wg's and have seen no difference between the 2. Please help!!!!

If anyone has any advice I would greatly appreciate it. Timing was set right plugs are new and gapped. 255 fuel pump. Just wont hit full boost.

[mp3]

Check your tps make sure its set right. Even though you mite have the throttle to the floor the tps mite be telling the ecu that its not.

[RBflyer91]

Okay I'll check that out! Any advice on a quick setting of the tps?

[mp3]

You might have to run a goggle search on the voltage it should be set at. I had a similar issue with my rb it felt sluggish and that ended up being my problem how do you have the vacuum hoses routed ?

[RBflyer91]

As far as I know everything is right. BOV from intake manifold. WG from manifold. And the little nipple on the recirc pipe is blocked off. I have another fuel pump coming. I feel like the one I have is bad. The problem is inconsistent. I was able to floor it all the way through 3rd today. And on 6psi the car seems to haul.

So I'm gonna try fuel pump and see what's after that. Hopefully it will fix my problems.

[mp3]

Yea its possible but if the fuel pump was going out it would still boost , but would detonate due to lack of fuel. But I hope you get it fixed I've been working on mine for about 6 years. I got a few parts layn around also so if u need something just tex me 252 955 9874 mike

[RBflyer91]

I guess I should have updated. I now had a boost controller and got the wg right. So now I am at roughly 6psi. My problem is intermittent. Earlier I went out and third gear pulled all the way up. But just once.

Also, the pump I have is used. I bought it from someone who said they had used it for one day of dyno tuning and needed more fuel so he took out this pump.

I'll give it a shot. I've tried 3 MAF's and 2 FPR's. We have checked timing too. So I feel like it's either fuel pump or ecu. I figured I'd start cheaper lol.