S/C engine having trouble and codes

I've been having some issues with my 2002 Tacoma 4 door 4x4. I put a SC on it. the truck ran great for a while after changing some vacuum hoses around. Then the truck started smelling like gas constantly and jerking while trying to accelerate and would hesitate and semi stall when driving. so I thought leaky injector. changed out injectors and stuck a new fuel pump on and truck still did the same thing. hard to start like might have to crank 4-5 seconds 3 times and pump peddle. still hesitation, rough idle, running rich fouls out plugs instantly blows black wet soot out the tail pipe. all the same issues its had. they just started kinda piling on. i have a p0300 code and a p0325 knock sensor code as well as P0172 code. STFT is -3.9 and LTFT is -30.5 gas mileage has been like 8MPG. I like to try and fix stuff my self. i checked for vacuum leaks with a can or 2 of carb cleaner nothing there. i need some input. I thought maybe ECM or its jumped time. you guys got any ideas?? I'm not getting rid or the truck I just want it fixed.

 

@eon_blue
Hope you can help this member. You are the only one I know that has a supercharger on a 1st gen.

 

Have you checked the fuel pressure regulator? Pull the vacuum line off of it and see if it has gas in it if it does the regulator is bad.

 

I have lots of ideas... mostly they start with, "Hold my beer and watch this..."

Oh... you truck...

I think we can safely say there's a fuel issue, the question is, what's causing it. Not sure if an 02 reports individual cylinder misfires or not; if it does, then you need to see which cylinders are misfiring. If it doesn't pull the plugs and look at them and see if they're all equally bad, or if it's specific ones. It sounds like maybe your ECU isn't controlling the injectors correctly. It may also be a spark issue; have you verified spark at all cylinders?

 

I haven't checked spark at all cylinders. I have swapped coil packs and wires 2 complete sets I have lots of extra parts accumulated. They all are so fouled its nearly impossible to tell what's the worst one. Beer in my shop is almost as important as oil. I have a 1998 Tacoma limited 4wd that runs well. The SC was on it before the 4 door SC swap. will the ECU swap over to my 02 from the 98?

 

Okay, so if all the plugs are fouled, we're looking at least as far back as the ECU, because it's [probably] controlling all the fuel equally. So, what's causing the ECU to improperly control the injectors. O2, MAF, and ECU itself, and especially the wiring & connectors need to be looked at.

 

I cleaned the MAF I have a new one I'm going to stick in tonight. I stuck a new upstream 02 in and none of that did anything,

 

But did you verify the power, ground & signal (and heater for the 02 sensors)? The OBDII only knows that it's not getting a response from a particular sensor, it doesn't know why. VERY common, especially on older vehicles for connectors to corrode, or conductors to chafe/fray/break, causing shorts, etc. It should set a sensor code of some sort, but it won't always.

Start by checking supply for the 02 sensor, then the MAF, and move down the line. Make sure you use a good quality incandescent test light to check grounds; preferably something with >2 amp draw, do NOT an LED test light or DVOM.

 

Possible the supercharger is venting air, and your issue isn’t so much excess of fuel but lack of complimentary air?

This sounds familiar to when a turbo vehicle pops an intercooler hose. All the fuel in the world is going into the cylinders but the air isn’t showing up to the party.

Otherwise I concur with the general consensus this sounds like a fuel/air issue.

 

total miles ???

what tune are U using

the ECU is reading & adjusting for matters that AINT Stock

 

I checked compression, checked spark on plugs, coils, checked fuel injector pulse, checked the MAF, IAC valve, up stream 02 sensor(there is no code thrown for 02 sensor), fuel pressure regulator was good, fuel pressure was good. All things still the same. Knock sensor codes and multi cylinder misfire and the too rich codes are all that's showing up. Knock sensors will be in today been pushed back a few times on shipping. (covid reason they say) ECU will be in next day or two also. I don't know how to check and see if the supercharger is venting air? I don't hear it.

 

truck has 350,000 miles and I am using an innova code reader a cheaper one.

 

Truck is fixed. After checking all of those other sensors and hopeful fixes it ended up being knock sensors. Runs like a champ. What a job it was. Glad I replaced the lower gaskets they were starting to seep after 20 years. Ready for another 350k now. Thanks for help dudes.