car running pretty lean, stock setup

[t4-teg]

I just got the car together, and got the WB installed, and the car is running pretty damn lean. When the car is fully warmed up with 93 octane gas the AF gets as high at 14.5:1 in boost (10psi). It usually stays around 13.4ish:1 fully boost, which is still pretty lean.

My setup is ported 2g mani, ported 2g o2 housing, 3'' dp, stock 14b, stock IC and piping. I also have the stock intake and MAF. I took the filter off the MAF and it looks pretty damn clean and newish looking. No wires cut, or anything, no BS honeycomb mods, its stock. My autometer gauge(hooked up to FPR vac line) reads 10psi, and creeps slightly in higher gears to around 12-13psi by redline.

The AEM wideband has a brand new sensor, so I know its not that. Im running stock pump, stock rail, injectors, ect.. The fuel is STOCK. I dont have a datalogger, or any way to moniter the engine, except the WB and boost gauge.

Not sure if it has a boost leak, the vac holds very steady at 20 in hg. I would think a boost leak would make it run richer anyway..

Has anyone else had this problem? It got so bad, the tip of plug #3 looked like it was melted slightly, which is NOT good. That scared the shit outta me, so ive been driving around staying completly out of boost for now.

 

[jjgrizz73]

Yes, your idle should be about 14.x and way more rich under boost. Change the FPR which is easy then look into the pump. I'd throw something like an evo/190 in it. Doesnt hurt to have that upgraded.

 

[t4-teg]

If I do the pump ill be doing a TT supra pump. Cheap and bolts right in, or so ive been told.

Im trying to get ahold of someone with a stock FPR to try out.

 

[jjgrizz73]

Whats the flow of the tt supra pump?

 

[t4-teg]

I believe its rated at 260lph.. Although I may go with a 190lph, money is tight right now, and Im not sure if I can afford a 255 or supra 260 pump and the FPR

 

[jjgrizz73]

with that much of a flow you will certainly need a AFPR not just the stock fpr. The evo 8 fuel pump you can pick up dirt cheap, fit right in and flow damn close to the 190lph. You wont need an AFPR with it either

 

[Demon33]

I believe its rated at 260lph.. Although I may go with a 190lph, money is tight right now, and Im not sure if I can afford a 255 or supra 260 pump and the FPR

You will definitely need an AFPR if the supra pump is in fact a 260lph. I rewired my 190lph awhile back and although many people say that you don't need an AFPR with it, once I installed my fuel pressure gauge I could see that my base fuel pressure was at 45 PSI! Stock 1G fuel pressure is supposed to be at 36-38 PSI. I installed my SX AFPR and was able to get the fuel pressure down to normal.

 

[t4-teg]

Would I be OK if I used a 2G FPR? That would up the pressure a little bit, or should anyway.

 

[jjgrizz73]

No, still would need the AFPR with the supra one. like I said it isnt needed for the Evo or 190 pump

 

[t4-teg]

sorry I wasn't clear. I meant, can I use a 2g FPR with my stock pump? That *should* rise the pressure a bit, and hopefully make it run a little bit richer?

 

[Demon33]

sorry I wasn't clear. I meant, can I use a 2g FPR with my stock pump? That *should* rise the pressure a bit, and hopefully make it run a little bit richer?

Yes, you are correct. The 2g FPR will raise your fuel pressure to 43 PSI, if it fits your fuel rail. I'm not certain if there were differences between the 1g and 2g rail as far as the FPR is concerned.

At 43 PSI you 'might' run a bit richer. At anything less than WOT the ECU will still try to maintain the air-fuel ratio using the O2 sensor. So as long as there is enough 'room' for the ECU to adjust, it can correct for the increased pressure and you may not see the results you're looking for. However, WOT is another matter, as the ECU doesn't use the O2 sensor for calculating fuel delivery. Here, you may see a richer mixture because of this.

Hopefully, someone with more knowledge on this will chime in. I'd like to know as well.

 

[t4-teg]

cool thanks man.

 

[dylnwit]

Another thing that I can think of to look into would be clogged injectors. How do your plugs look? And is your sensor for the wide band mounted far enough downstream from the turbo? Most of what I've read about them recommend being mounted at least 2 feet away from the turbo.

 

[t4-teg]

Mines about a foot to a foot and a half from the turbo. That doesn't matter, have it that far from the turbo is just for heat reasons.. With the stock O2 sensor being mounted 2'' from the turbo, I don't see a problem with the AEM sensor being mounted a foot away...I'm pretty sure the sensors are made by the same manufacturer.

This thread is not for that though, please, I don't want a argument thread about that.

 

[dylnwit]

Mines about a foot to a foot and a half from the turbo. That doesn't matter, have it that far from the turbo is just for heat reasons.. With the stock O2 sensor being mounted 2'' from the turbo, I don't see a problem with the AEM sensor being mounted a foot away...I'm pretty sure the sensors are made by the same manufacturer.

This thread is not for that though, please, I don't want a argument thread about that.

Sorry, was just trying to pass along what I've read on other parts of the site, wasn't trying to start an argument either, I was just somewhat thinking out loud there, my bad.

 

[Turbo Talon DL]

Change the stock FPR before you try anything else along with the fuel filter. Those two things will be the most cost effective preventive/corrective maintenance that you can do in order to fix this thing. I had a stock FPR get stuck shut meaning I would run pig-rich under vacuum. I actually fouled out some plugs on a freeway once because of it. I used an old style AFC to lean everything out and it worked. Once I replaced the FPR I was running TOO lean under vacuum so I had to richen it back up. If those two things dont fix it I would be guessing at either the pump, clogged injectors, or maybe an injector drive circuit as the last thing. Your engine vacuum is GREAT so I wouldnt think your vacuum lines were going bad.

 

[Demon33]

Another thing that I can think of to look into would be clogged injectors. How do your plugs look?

Good one. A clogged, partially clogged or inoperative injector would affect the O2 readings. By not injecting the proper (too little) amount of fuel, the O2 would show a lean condition. Conversely, too much fuel (ie. leaking injector) would show up as a rich condition.

Let's look at this a bit more. I'll throw this test/theory out there. Someone please correct me if I'm wrong. Assuming all injectors are good, if you were to disconnect one injector electrical connector at a time while the engine was running, you should notice a definite change in the idle characteristics of the motor as each injector is taken 'offline'. However, if one injector is bad or clogged, that change in idle 'should' not be as pronounced when it (the bad injector) is disconnected.

I would also think that the O2 readings would be different between disconnecting a good injector versus disconnecting a bad one. Food for thought...

 

[t4-teg]

Sorry, was just trying to pass along what I've read on other parts of the site, wasn't trying to start an argument either, I was just somewhat thinking out loud there, my bad.

Not a problem man. Thanks for your insight. As for the injectors, that is a good way to test. Im pretty sure I can shut the injectors on/off with my pocketlogger, as soon as I figure out how to use it.

ill have to find a FPR around here I can test out.

Thanks Everyone for your help!

 

[toofast82]

never used pocketlogger, but mmcd can do this as i see you have questions about both in another post

 

[t4-teg]

OK, I might have figured something out. I was monitoring the voltage with mmcd and at idle the voltage was at ~10volts. I started checking all wiring/battery/ect.. and found the connector that goes to the alternator has two wires, and both of them looked like they were cut and twisted together and covered in oil. I connected them properly and cleaned all the oil off, now at idle the voltage is 13volts. Before I did this, at idle I would just get 3 --- meaning too lean to register. I think the gauge didn't have enough power going to it and read leaner than normal. At idle now its reading about 15:1. I took it for a spin, and at WOT instead of reading 15-16:1 it now reads 13:1.. I know still lean but not as bad..

My question now is, I hooked the power and ground wires with the power/ground of the cigarette lighter. Does this power wire have enough voltage to power the AEM sensor? I left my multi-meter in FL, so I guess ima have to buy a new one.

 

[jjgrizz73]

I have my aem tru boost power wire as well as the lc1 wideband on the cig. lighter and it works fine. Its a 12v source just like any other power in the car.

 

[t4-teg]

cool. good to know. Thanks.

 

[t4-teg]

RESOLVED!!!!

I did a fuel pump re-wire on my car today, which went surprisingly well. I kinda did it my own way, with a mix of all the re-wire articles... Anyway.. The car runs in the high 10's low 11's AF ratio in boost (8-9psi). It runs perfect at idle and cruising, right around 14:1.

It feels like its running wayyyyy better, with less timing being pulled.. I really have no idea now, becuase just the other day my logger kinda stopped logging. idk, one more thing I gotta look into.

I just wanted to let everyone know my fuel pump is getting 14 volts and the car is running perfect, for now.