Bogging on the highway...

[NICONick]

OK, so I just bought another S13 for $1k and it's got some miles but wat S13 doesn't. Anyways, I got it home and for the first time took it on the highway today, but at like 65mph it starts to bog a little bit and no longer maintains speed and starts decelerating. If i downshift or blip the throttle, it seems to go back to normal and doesn't bog down. It isn't until Im cruising again that it starts to do it... problem seems intermittent. Car also seems to be running a little rich. Any ideas?

[NICONick]

Nothing...?

[biggie]

Vaccum leak, bad O2, bad fuel pump, replace fuel filter, etc, etc.

[NICONick]

A bad IACV wouldn't cause this would it? I'm having the "stalling at redlight" problem and I'm assuming that it's a dirty IACV. I'll check for vacuum leaks and it's not the fuel filter bc that was just replaced with a Z32 fuel filter.

Wouldn't a bad O2 throw a CEL ?

[biggie]

IACV would cause the stall at light and when going from higher RPM to idle, but IACV would not affect cruising at highway speed.

BAd O2 wouldn't always cause CEL, could just be bad enough to run rich/lean. More likely its not O2 though if running normal at other times.

[NICONick]

Does run a little rich... How would I go about checking the O2 sensors if Im not throwing a code?

[biggie]

If you actually suspect the O2, just replace it, only like $15 for a new Bosch at parts store I believe.

If you are running rich and its not the O2 could have air/vaccum leak, FPR could be bad, or leaking around injector maybe.

[NICONick]

If you actually suspect the O2, just replace it, only like $15 for a new Bosch at parts store I believe.

If you are running rich and its not the O2 could have air/vaccum leak, FPR could be bad, or leaking around injector maybe.

Correct me if Im wrong but don't our cars have more than one O2 sensor? Also, FPR? Sorry I'm not familiar with that terminology...

[gijoe392003]

FPR = Fuel Pressure Regulation and yes, only one O2 sensor. If it feels like that car is struggling to go past 65, then that is definitely a fuel issue. Most likely the fuel pump. If it feels like a fuel cut and the engine doesn't respond, then that is the 4th or 5th gear sensor.

[NICONick]

FPR = Fuel Pressure Regulation and yes, only one O2 sensor. If it feels like that car is struggling to go past 65, then that is definitely a fuel issue. Most likely the fuel pump. If it feels like a fuel cut and the engine doesn't respond, then that is the 4th or 5th gear sensor.

It will go past 65... just cruising at those high speeds is when the problem becomes apparent. Would the fuel pump be cutting in and out? I feel like fuel pump either works or doesn't work... Almost feels like a leaky injector...?

Engine doesn't die and come back. It just feels like it loses power and then will come back if i downshift into 4th or blip the throttle a few times, and sometimes it even comes back on its own...

[gijoe392003]

I know I am having a problem with my fuel pump being clogged by crap in the tank. I just suggested the fuel pump because of my issue but it could be the filter, FPR, or injectors.

[NICONick]

I know I am having a problem with my fuel pump being clogged by crap in the tank. I just suggested the fuel pump because of my issue but it could be the filter, FPR, or injectors.

Thanks. Gonna try cleaning the TB and MAF today and see if that helps at all. Also, I don't know if this problem has anything to do with the bogging or the IACV prob that Im having as well, but in the mornings (its cold in NJ), the car has trouble running. I'll go out to start in to warm it up and when I come back out to go to work it has stalled. Today I waiting in the car to see how long it takes the car to do it and within 2 minutes the car stalled out. RPMs dropped and fluttered around 500-600 and then it stalled. Does this have to do with the bogging prob Im experiencing or my dirty IACV?

Sorry for the long explanation, just wanted to be as detailed as possible for responses. Thanks NICO!

[biggie]

That is the IACV (idle issue) the bogging has nothing to do with IACV.

[S13_RB25]

It could be miss fire caused by a vacuum leak?? Oh also where NJ are you??

[asoomal]

I doubt it's the O2. The ECU doesn't even use it much, you can run it disconnected and you wouldn't notice anything. I ran one without one for a year cause I was too lazy to hook it up (DC Headers).

[NICONick]

It could be miss fire caused by a vacuum leak?? Oh also where NJ are you??

Im from South Jersey, Cherry Hill, are you from jersey?

I doubt it's the O2. The ECU doesn't even use it much, you can run it disconnected and you wouldn't notice anything. I ran one without one for a year cause I was too lazy to hook it up (DC Headers).

I agree, had DC headers too.

Also, cleaned the MAF and TB, just to clean it and see if it changed anything. It seemed to crispin up my acceleration, but still is running rich and feels like it would bog on the highway still. I also sprayed some TB cleaner into the intake tube that goes to the IACV and it seemed to help a little bit, but i think the IACV just needs to come out and b cleaned. Also, sending out my extra set of injectors to Deatschwerks to be cleaned. Hopefully this helps the bogging prob.... Any other ideas?

[asoomal]

Test the Coolant Temp sensor, when it malfunctions it causes the car to run quite rich.

[S13_RB25]

It could be miss fire caused by a vacuum leak?? Oh also where NJ are you??

Im from South Jersey, Cherry Hill, are you from jersey?

Yea I'm in Burlington township after I get my s*** running we should meet up...

[NICONick]

Yea I'm in Burlington township after I get my s*** running we should meet up...

yea sounds good jsut pm me or something

[NICONick]

Where is the cheapest place to get the Walbro Fuel Pump... I thought there was a sticky for one for $85.99, but I searched and couldn't find it. I'm replacing wires, plugs, cap, and rotor today to see if that helps but if not I am going for a new fuel pump.

[S13_RB25]

Well i looked around walboro is $100 but i found isis and a circuit sports 255 lph fuel pumps from $70 to $75. The isis on http://www.240sxmotoring.com/ishi255ltfup.html and the circuitsports on http://www.frsport.com/Circuit-Sports-2 ... 12477.html

Hope that helps!!

[NICONick]

Well i looked around walboro is $100 but i found isis and a circuit sports 255 lph fuel pumps from $70 to $75. The isis on http://www.240sxmotoring.com/ishi255ltfup.html and the circuitsports on http://www.frsport.com/Circuit-Sports-2 ... 12477.html

Hope that helps!!

It does! Thanks! Anyone know if it's worth saving the $30 to go with those brands as opposed to Walbro?

[Razi]

Never skimp on fuel.

If it ever screws up, your engine could run lean and kill itself.

[SC90S13]

possibly a clogged ERG system

[NICONick]

possibly a clogged ERG system

ERG? Did you mean EGR?