Boost over 12psi NOT ALLOWED!!!

[Enilator]

As you can see by my mod list Ive done all the stage 1 mods except the fuel pump. The problem I'm having is with increasing the boost past 12 PSI. The car runs strong around 12 but if i turn it up it almost feels as though the ECU is retarding timing?? The car seems to fall on its face if I turn it up to 14 or so, but if i turn it right back down to 12 NO PROBLEMS. With my mods shouldn't i be able to run higher boost? I am running 91 octane and Ive noticed no change when i raise the octane level. Theres no boost leaks.The things that come to mind are: ECU retarding timing, BOV leaking, MAS honeycomb removal,lean fuel mixture??? If i was to buy a datalogger (ebay) would this tell me what is going on?Or has anyone else had a similar problem and had a fixable outcome? Thanks for any help guys!

 

[Thomas91169]

if you buy a palm/pocketlogger off ebay it will be able to tell you if timing is being pulled.

 

[Synapses]

if you buy a palm/pocketlogger off ebay it will be able to tell you if timing is being pulled.

Watch out that you don't get screwed with some ebay cheapo knock-off

 

[sweet97]

As you can see by my mod list Ive done all the stage 1 mods except the fuel pump. The problem I'm having is with increasing the boost past 12 PSI. The car runs strong around 12 but if i turn it up it almost feels as though the ECU is retarding timing?? The car seems to fall on its face if I turn it up to 14 or so, but if i turn it right back down to 12 NO PROBLEMS. With my mods shouldn't i be able to run higher boost? I am running 91 octane and Ive noticed no change when i raise the octane level. Theres no boost leaks.The things that come to mind are: ECU retarding timing, BOV leaking, MAS honeycomb removal,lean fuel mixture??? If i was to buy a datalogger (ebay) would this tell me what is going on?Or has anyone else had a similar problem and had a fixable outcome? Thanks for any help guys!

If you can afford it go with the Scanmaster from www.fullthrottlespeed.com plugs into the diagnostic port and mounts on your dash and gives you info like a logger like 02 voltage, knock, timing advance, coolant temps and a dozen more pieses of data as you are driving. Even has a "G-Tech" feature for 0-60, 1/8 and 1/4 mile times. Mark

 

[terminaltsi]

that's really weird because on all my dsm's over the years i've been able to run 15psi with no fuel mods at all and get full timing. i'm running an e316g on my galant with a stock pump and 625 cc injectors right now at 15psi and i'm getting full timing.
of course i have to ask why you are running 91 octane?
the problem is, the ecu won't see you switch to 93 until you run at least a couple hundred miles on it. only then will it give you full timing if it is indeed being pulled. i've never run 91 and never plan to. the cost difference over 10 gallons is 1 dollar.
i'm not saying 91 is your problem, the car should be fine at low boost like that on 91 but it's always possible.

 

[JiveMasterT]

my car runs at 15psi with only a rewired fuel pump... i think you could probably run 15 as well... there seems to be something else wrong with your car.

 

[Enilator]

There is also something i forgot to put in there. The car seems to run rich cause it has some black smoke on the bumper where muffler dumps. Is it possible the ECU is messed and dumping to much gas in and basically flooding it out? I have had computer problems and had to go back into it and solder in a wire to make a through connection for one of the capacitors. Just a thought................

 

[Enilator]

This morning was a unusually cold morning (50 degrees). I wondered if this would tell me anything so i put it up to around 15 psi. I had no fall on its face syndrome whatsoever until i was almost to work. (car at operating temp) I would think this would rule out the ecu? i turned up the boost and hit fuel cut for the first time, but the turbo made a different kinda whistle, is this due to just higher boost? I was the one that rebuilt my turbo, is it possible that it is not totally balanced and only does this at warm up? I think it was up around 17-19 psi when it did this. Also i would think it would rule out the MAS cause the air was the same temp all the way to work and it did it when it got warm. I don't know, I'm just throwing out ideas cause this is aggravating.

 

[v2ner]

i wouldn't want to go past 15 psi w/ stock injectors and pump.

 

[oldman]

Theres no boost leaks.

How do you know this? Visual inspection or a real leak test? If leak test, how much pressure was the system able to hold and for how long?

BOV leaking

If you did a test, how can you not know this?

MAS honeycomb removal

I do not like this free mod at all, at least not without a logger. Have you tried putting the honeycomb back and see what happens?

 

[4G63 For Me]

of course i have to ask why you are running 91 octane?

He is in Kansas and much like my location, the highest octane at 95% of gas pumps is 91 because of our altitude. Cars don't knock as bad at higher altitude, thus we get lower octane.

As to the original poster, you never said whether or not you did a boost leak check, and if so, how much did it hold and for how long. I was having the same problem as you just yesterday (with more boost, though). Couldn't go past 18 or so. I did a boost leak check on my car and found one of the silicon couplers had torn. I replaced it and it feels like a whole different car and I easily hit 25 PSI.

 

[Enilator]

As for a leak test its been about a month, but i was having the same problem then. If it was a boost leak would it just start leaking when the car gets warm? As for pressure and timelength i put it up to like around 20-25 i believe and it held for around 2-3 mins if i remember correctly. Thanks for all the help guys!

 

[thegreatms]

If you can afford it go with the Scanmaster from www.fullthrottlespeed.com plugs into the diagnostic port and mounts on your dash and gives you info like a logger like 02 voltage, knock, timing advance, coolant temps and a dozen more pieses of data as you are driving. Even has a "G-Tech" feature for 0-60, 1/8 and 1/4 mile times. Mark

I would never spend $250 on a scanmaster. For 80$ you can get a palm and datalogging wire on ebay. Add the freeware MMCD and you can read all the things you mentioned (no G-tech feature).

250$ is a major ripoff.

 

[4G63 For Me]

Have you tried putting the honeycomb back and see what happens?

That would be my next suggestion then as well.

A datalogger would definitely help. If I had to take a guess, I'd say you're sucking in too much air from the removal of the honeycomb and the ECU is pulling timing from knock.

Just a guess, could be wrong. Not sure why it didn't happen until you were just about to work. Cars do weird things when they aren't running right.

 

[Enilator]

Yeah i agree, i will try that tonight when i get home tonight and see if it has any effect. I have had this problem ever since i got the car running after i first bought it, but just left it alone cause i didn't have much time to tinker. But now i do so I'm all over it!! and it sucks to only be able to boost 12psi, I'm guessing i would get a little better in the 1/4 may since the new exhaust and muffler and 15psi i could hit high 13's?

 

[Enilator]

Well i put the honeycomb back in and it had no effect. One thing it did fix was when the motor reved high it would spit and sound horrible coming back down to idle, so at least thats fixed. But now i turn it up to 15 psi and it seems to hit fuel cut (HARD jerk) and i let off. I purchased a datalogger off of ebay and i guess when that comes ill check it all out unless anyone has any other ideas??

 

[MNGSX]

Direct wire the fuel pump. Change the fuel filter.

 

[Enilator]

Im not sure if i put that in my profile but i have rewired the fuel pump. And the fuel filter has about 4 thousand miles on it, should i replace it anyways? I guess, come to think of it the car was down for about a year, maybe rust in the tank? But i do have black smoke on my rear bumper (sign of running rich?)?

 

[v2ner]

black smoke is a sign of runnin rich...most of the time. otherwise it's blowby. low 14s is probably a more realistic timeslip.