Car Bogs Out over 14LBS Boost

[mydgaf]

I own a 1990 Mitsubshi eclipse with a Big 16 G turbo. The car runs fine at factory boost of 14lbs. When I turn the boost up to 17 or higher I can't go over 4500 rpm with out the engine bogging out or blowing a cloud of smoke out of the exhaust at high boost. I have coverd all the basics for leaks, I do not have a fuel computer could this be the problem. Not enough fuel and to much air at high boost? Just had a new head put on and had the engine rebuilt. Any ideas to fix this problem would be great. Need help driving me nuts!
Thanks!

 

[HustlerTalon]

The car bogging out on high rpm's can be a boost leak somewhere. Do a boost leak test to see where its at. Smoke coming out of the exhaust is usually because you are running rich...what do you have in fuel upgrades???

 

[burtreynolds]

I own a 1990 Mitsubshi eclipse with a Big 16 G turbo. The car runs fine at factory boost of 14lbs. When I turn the boost up to 17 or higher I can't go over 4500 rpm with out the engine bogging out or blowing a cloud of smoke out of the exhaust at high boost. I have coverd all the basics for leaks, I do not have a fuel computer could this be the problem. Not enough fuel and to much air at high boost? Just had a new head put on and had the engine rebuilt. Any ideas to fix this problem would be great. Need help driving me nuts!
Thanks!

Define "bogging". Is it popping and stuttering, just not revving any highter, or what?

 

[95blackGsTurbo]

By looking at your profile you have a fuel pump without a AFPR and no injectors. You are maxing out the injectors and running dangerously lean. Keep it around 14psi until you get an AFPR, bigger injectors and some fuel control. Also make sure you are recirculating that HKS BOV.

 

[acsbmx_1]

Doesnt 14psi sound a little high for factory boost. I've read in my owners manual that is 10-11?

 

[kelvinb]

probly a boost leak, look around.

also i seen with my wideband, w255/15psi/450s and stock fpr i was getting 9:1 afr's. im pretty sure hes not lean.

 

[laserspeeddemon]

Depending on the pump he should be able to run 19 psi. I've run my talon with a Walboro 255 and no AFPR and injectors for a while now.

My suggestion, check the compression. You said you've done boost leak, and if you've done it correctly (which is not likely). Thats would be your next step.

 

[mydgaf]

Thanks for all the suggestions. To help you all out a little more I do have 550 injectors and fule PSi regulator. I do have the math box where I can control fuel cut and lean and richness of the fuel. The problem is during the day time I can set the boost at 17lbs and it runs good. But there is still some boging when I down shift from 3rd to second and step on the gas it bogs. At night time when it is colder outside it bogs very bad.

Bogging: when I drive down the road and the turbo gets up to 17lbs of boost and my turbo kick in at 3000rpm peak boost at 4500 -5500 rpms the car cuts out for a second and makes a backfire and when this occures it blows out some smoke. This happens at full throttle. When I run at half the throttle and let the boost and rpms run up together it helps a little. At this time I am running the car at 14lbs with no problems or smoke day or night. 16lbs or higher I get the bog out condition. My concerns if I am running to much air and not enough gas at higher boost due I need a fuel computer to adjust the fuel trim at higher boost. I have a high flow fuel pump, think a 255 fuel seems to be their. Is the cpu in the car not allowing me to give the engine the propper amount of fuel. Any thoughts with all this information would be great. Thanks to all of you for your help!

 

[laserspeeddemon]

when I drive down the road and the turbo gets up to 17lbs of boost and my turbo kick in at 3000rpm peak boost at 4500 -5500 rpms the car cuts out for a second and makes a backfire and when this occures it blows out some smoke.

Sounds like fuel cut, a strong indication of a boost leak.

 

[Sneakyninja83]

I have a 99 eclipse gst and when I use full throttle, my car putters and sputters like its not getting enough fuel or maybe too much. Not sure what problem is and need some help. If i gradually apply throttle, then the acceleration is ok but I can't floor it.

 

[Spoolin18]

Fuel cut and possibly a boost leak.

 

[9!'clipseDOHC]

I have a 99 eclipse gst and when I use full throttle, my car putters and sputters like its not getting enough fuel or maybe too much. Not sure what problem is and need some help. If i gradually apply throttle, then the acceleration is ok but I can't floor it.

4.5 year thread revival!! How much boost are you running? Have you done a boost leak test? How old are your plugs and wires (are they NGK)? What octane gas are you using?