Bspec18

When im driving for a while the car tends to bog and stumble when its about to enter boost, When this happens My A/F gauge is jumping more than usual, Then the A/F Gauge finally goes to lean till the light turns off if i continue to keep on the throttle. This has also happened just sitting at a light.

Can someone point me to some things to look for ?

From what I have searched it could be a clogged Fuel filter (replaced 2yrs ago) And A bad 02 sensor, Is it possible to have a bad o2 with out throwing a CEL ?

My fuel managment for now is: RC 310cc, AEM FPR, MSD Inline, Vortech 12:1 FMU and a Walbro 255 lph hp.

Bspec18

Well i just did another search and it does seem it just might be the o2 sensor, but i have another question:

Is it possible to have a bad MAP Sensor with out throwing a code ? I throw a CEL 03 once in awhile if i continue to push the car in boost when its already in the lean

Bspec18

Anyone ? I could use some advice

CzanSOHC

sounds like to much fuel. At idle your stock ecu is have a hard time idling those 310cc injectors since it was programed for 240cc.

Bspec18

I don't think so becuase when the car does start acting up it goes to the lean and when it does jump in the rich you can feel a surge of power. I have a HKS S-AFR (basically a S-AFC) i've added fuel as high as 20% and still running lean. Any other solutions ?

Bspec18

Ok today i have replaced the o2 sensor. It was driving fine for awhile but as soon as the car warmed up it started the same problems again. So I am convinced it is not the 02 Sensor.

It seems that this problem happens when the car is warm or hot, But i've already replaced the themostat and Fan switch New coolant using Water Wetter mix with Prestone and water. Also I have a Fluidyne Radiator.

What do you think the problem is ?

Mase

I'd seriously think about upgrading your Fuel Management.

Bspec18

I am going to that is why i'm switching to a OBD-1 ECU so that I can run Hondata. Im just asking for a temporary fix, It really sucks to have this problem throuout the boost. I kno it can be fixed because their our hundreds of people boosting 6+ pounds with out having this situation

Bspec18

Anyone please ? i've checked every possible thing on my car. IM thinkin or replacing me MAP Sensor as a last resort

Mase

id be careful w/ shitty fuel management, is it worth risking blowing your motor not waiting for proper fuel management?

Bspec18

I agree with proper fuel management. But i need to make money first before i go ahead and do that. I seriously wouldn't bother this board if this didn't annoy me. I can't even boost 6psi without all this stumbling and bogging, it sounds like the car is running on 2 cylinders I did a compression check and everything is fine.

So pls. I understand proper fuel managment i.e Hondata or AEM EMS etc... I'm just asking for a solution for now so i can drive to work and back with out all this embrassing bogging and studering. My car ran fine before, but now ????

Mase

do you have a fuel pressure gauge, my guess your fmu is sticking

you might wanna try taking out the fmu and seeing if that solves the problem

Mase

also, how do your plugs loook, but the look of it, you're probably running hella rich w/ 310's and 12:1 fmu

Bspec18

I would think so too... But i've checked them and their a redish color and I've pulled them like3 months ago before and they were white. I have them gapped at .28 and i've had 2 different tuning shops play with the timing and i've gotten a lil bit smoother in acceleration.

Thanx for replying back MASE Your write-up on the JDM conversion was a big help btw

Bspec18

I'll try the new FMU Disc i can get one for free anyways, But also another reason i was thinking i might be running lean is beacuse i kno the Autometer A/f gauge is basically "a Light Show" But I kno At full throttle GREEN is RICH but when this problem Occurs it Stays in the red.

I forgot to metion the FPR i'm running now is a AEM so it has 1:1 so
13:1

Mase

i usually dont trust the normal afr gauges, but if you think its running lean, go ahead and switch fmu disc's

does it smoke at all when it hesitates? if it runs really rich, you can either smell it or it will smoke....

im sure you've already done this too, but make sure the wiring for the inline pump is correct and didnt come loose.


If you have any further questions, and i dont see this post, hit me up on PM.


Mase

P.S. thanks for the props. i miss my car dearly.