Running rich, cannot figure it out

[98Gate]

As luck may have it, my LTFT was at -10.9%. I've got a recently installed JDM engine and I had Motorwest injectors put in. Now, I might have fouled O2 sensors from the previous engine's coolant consumption, and I also do have a bit of an exhaust leak, so I wouldn't let my situation completely throw you off That said, I did come across this thread.

Just a moment...

Hmm I might give motorwest a call today, ill let yall know… timmy the tool man gave them high praise and he usually doesnt lead one astray


-98Gate

 

[T4R2014]

I'm going to hold off blaming the injectors first since it runs so well. I'm pretty suspicious of my catalytic converter and oxygen sensors, B1S2 voltage waveforms look very odd with inconsistent amplitude. Being that these parts may have been fouled from my leaking HG, I think I'd rather throw some oxygen sensors at it first and then a cat if those do nothing.

 

[98Gate]

I'm going to hold off blaming the injectors first since it runs so well. I'm pretty suspicious of my catalytic converter and oxygen sensors, B1S2 voltage waveforms look very odd with inconsistent amplitude. Being that these parts may have been fouled from my leaking HG, I think I'd rather throw some oxygen sensors at it first and then a cat if those do nothing.

Can you post a pic of your data graph? I think I mentioned that I threw a p0420 code a couple of weeks ago. Cleared it and it came back. I have a suspicion of exhaust leak pre 02. It sounds like we are having similar problems. Both 98’ runners, im at 314k, similar components. Cat should in theory last forever but ethanol ruins them

 

[thegipper]

I had a similiar issue with my LTFT being -11% or so and it ended up being a bad o2 sensor and/or a crack in the exhaust right before the o2 sensor.

Here is my post I made. https://www.toyota-4runner.org/3rd-...er-after-car-wash-p0172-2.html?highlight=died

Post 24 is where I found the crack. I ended up replacing the o2 sensor that was near the crack and welding up the crack itself. It's hard to say for sure which one fixed it but the code never came back and my LTFT numbers have always been fine since.

I should add, my symptoms were exactly like yours. My truck also randomly died but would always restart and it was sluggish at low rpms (details are all in my post).

Hope this help.

 

[T4R2014]

Can you post a pic of your data graph? I think I mentioned that I threw a p0420 code a couple of weeks ago. Cleared it and it came back. I have a suspicion of exhaust leak pre 02. It sounds like we are having similar problems. Both 98’ runners, im at 314k, similar components. Cat should in theory last forever but ethanol ruins them

Can't seem to get the data logging to work in the app so these are just live screenshots at idle. It has 288k overall, 100k about on this Walker catalytic installed under a PO. Definitely sounds like it has a leak.

 

[T4R2014]

[MENTION=792518]98Gate[/MENTION] have you made any progress? None here so far, my P0420 came back after some city driving. I hear a decent exhaust leak, and I think it's at the downpipe connection to the cat. I got a new Walker cat awaiting install.

 

[98Gate]

[MENTION=792518]98Gate[/MENTION] have you made any progress? None here so far, my P0420 came back after some city driving. I hear a decent exhaust leak, and I think it's at the downpipe connection to the cat. I got a new Walker cat awaiting install.

No progress, in fact, its gotten a bit worse. LTFT was sitting at -14 at the light the other day. I am more curious about the motorwest injectors than anything. When work slows down I will pull the rail off and put the oem ones back in. My fuel economy has gone to crap. Im lucky to get 200 miles on a tank. Im doing a lot of city driving though. Any updates on your end?

 

[T4R2014]

No progress, in fact, its gotten a bit worse. LTFT was sitting at -14 at the light the other day. I am more curious about the motorwest injectors than anything. When work slows down I will pull the rail off and put the oem ones back in. My fuel economy has gone to crap. Im lucky to get 200 miles on a tank. Im doing a lot of city driving though. Any updates on your end?

Nope, haven't checked. My fuel economy tanked but that's also due to winter blend fuel and letting it warm up a few minutes via remote start. I found multiple exhaust leaks, but I think I need a new gasket where the driver side manifold connects to the crossover. Hopefully this can be done without too much struggling.

 

[2TH4IST]

That rear o2 looks sus. It should be damn close to a flat line, if your cat is working that is. But can be a exhaust leak too. Actually I just found one on mine. Blew out a gasket.

 

[T4R2014]

That rear o2 looks sus. It should be damn close to a flat line, if your cat is working that is. But can be a exhaust leak too. Actually I just found one on mine. Blew out a gasket.

I got a deal on a Walker cat and ordered some new Denso o2's while I was at it. Going to get them installed and see. Between that and a crossover reseal I think it will run quite well. Going to hold off on blaming the Motorwest injectors until then because it runs very nice despite all this.