Low pressure on acceleration

I have a 06 Tacoma 4cyl 2wd auto an after getting off interstate run it seemed to loose pressure at the gas pedal..I had put gas in it though it was showing I had some..still low pressure feel getting home.In park it runs perfectly fine an quiet.I had noticed a slight scent of fuel after filling up at station..

No codes an a tight fuel cap.
What should I look at 1st..fuel pressure ? Plugs? Compression? An where is the hose to T off of or to connect gauge to? An what psi should it be ? Anything with maf or other sensors to look at?
Last year a new fuel pump was put in .
Thanks

 

Fuel injectors aren't a sensor and those could be a culprit. They can be either clogged enough and not reaching optimal regulation or malfunctioning.

 

Not sure what you mean by low pressure? You mean it's struggling to accelerate?
Is it misfiring or does it just rev and not accelerate?

 

Slow to accel as you give gas.Though it idles perfectly in park an at light .I was not attempting to go fast at all to get home after it happened an I only accelerated lightly to make it home safely..And after getting off interstate.then turning at light, as giving it gas to go on ,up to 45mph it was like no pick up at all as you attempt to go faster .

 

Maybe converter getting plugged?

 

Does the engine sound as if it's struggling?

Certainly could be a converter that is restricted, only way to prove it would be to do an exhaust backpressure test by removing the AFR sensor and using an exhaust backpressure gauge.

 

Thanks.Woluld monitoring the 02 an afr readings as running help to prove if it's the converter ,an does plugged converter give gas smell..?
I will be checking fuel pressure too.Where do I T in at under hood? An what should it read as running ,and after 5 minutes, after you turn off engine?

 

Monitoring AFR and fuel trims would give you direction, if they are rich when it's sluggish I'd be checking for a restricted converter but if they are lean I'd be suspecting low fuel pressure.

To check fuel pressure you have to tee into the line at the quick connect where the line from the engine connects to the line on the frame, should be 41 psi +/-1 and should not drop below 21 psi for at least 5 min after the engine is turned off.

You need something like this to tee into the line.

$33 BETOOLL Fuel Pressure Test Kit 0-100PSI with 9.497.896.30 Fuel Line Fittings

https://www.amazon.com/dp/B07LF26ZTJ

This is where it is on a 4.0L, 2.7L should be similar.

 

Thanks .the fuel trim at idle stayed in range - 3% an up an down a bit but steady never over 10% ..I didn't watch it as driving though,but will..
I cleaned up an regapped the denso plugs cleaned up the throttle a tad rechecked gas cap an lines an checked that the air filter,lines,oil,were ok an ,made sure injector connections were secure an MAF ,TPS,were all in tact ,an hoses w no broke tubing..I also added Lucas injector cleaner an took for a run in city an it actually had more power driving ..an pick up was better..I haven't took it on interstate yet but plan to in a bit an then see what it does after I get off the exit .
TPS was 14% an most all other readings checked in normal..both cat temp readings were 400°on one an an near 500°on other reading.. after run..an 02 after cat ok looked ok too .

Maybe it was carbon on plugs , water or trash in gas or not a secure cap or combination ..but that doesn't rule out converter having some stuff plugging it up some ,I wouldn't think ..

If the Rpm an Power is good as I accelerate getting on interstate I doubt my fuel pressure needs testing.. but good to have the readings an location to T for future pressure tests..

Is this truck picky on using only TOYOTA gas cap ? I have a aftermarket on it..



--An on a good note..THAT FUEL GUAGE ISSUE I HAD MANY MANY MONTHS BACK- STAYED WORKING 100%OF THE TIME NOW!

WHAT I DID WAS FILLED TANK TO FULL ,..PULL OFF THE NEEDLE LITERALLY TURN KEY AN REPOSITION IT AT FULL TILL ITS EXACT.TWEEKING IT AFTER U TURN KEY... AN THEN USE THE TOP 50% OF THE GUAGE ALL THE TIME..IT NEVER FAILS AN STAYS ACCURATE ! .....VS USING THE FULL 100% OF GUAGE...

 

It did well on interstate..is Cat temp b 1( as driving 65mph ) an 2 normal to read temp of 1043° ?
An when accelerating fully is command purge reading of 100 ok? It lowers BK to 26 at regular 40mph steady drive ...

Still wondering on gas cap too..

Thanks

 

Catalyst temp is calculated, there is no actual temp sensor. Not really a useful PID to look at.

Purge command sounds about right, it's going to open more at higher throttle.

 

It looks to be in range of what converter temperature should be ..-during normal operation-, with potential spikes to 1200°F (650°C) under heavy load..

I don't think I have a clogged one either..by what this says -
If the converter becomes clogged or there's an issue with the engine's air-fuel mixture, it can overheat and reach temperatures above 2,000°F

 

Like I said the converter temp PID is calculated, it doesn't reflect actual temp.

Typically with a plugged converter you will have a severe lack of power and the engine will sound "constipated" but AFR will be normal to rich.