1sennafan

89 4runner 22re 5spd
I am so frustrated right now I could just spit!
Let me start with my almost latest issue first, THIS IS NOT AN IDLE PROBLEM! The motor will idle just great at 750 but lopes with slight throttle applied. I’m thinking it’s the “fuel cut RPM” because it fluctuates between 1600 and 2000 RPMs. From what gather the TPS is what activates the fuel cut RPM? That’s what the FSM test says it should do when connector is jumped. TPS tested out fine by the book. When I remove TPS connector it goes from idle to WOT with no lope, no hesitation, no problems. When I put it back on right back to the loping.
Does this mean even though all the numbers are by the book the TPS is bad? Any info on the “fuel cut RPM” would be helpful, as I don’t really have a clue as to why.
Now I digress.
It’s been six long days of trying to get it "TEXAS" inspected.
My 1st try it failed on idle HC at 332 ppm.
Here are the numbers:
High Speed Test RPMs 2602
Standard.........Current Reading
HC- 220................133
CO-1.20................0.91
CO2-.....................13.6
O2-......................0.9
Dilution->6.0 .........14.51

Low Speed Test RPMs 957
Standard.........Current Reading
HC- 220................332....FAIL
CO-1.20................0.58
CO2-....................12.9
O2-.......................2.1
Dilution->6.0..........13.5

So I replaced plugs, replaced wires, replaced dist cap, replaced rotor cap, checked vacuum hoses, oil change, Seafoam intake, bumped the idle up, leaned the air/fuel mix, put RXP in 94 octane fuel and drove about 30 miles on the highway.
Next morning I drove 10 miles on the highway and went back to retest and:
Here are the numbers:
High Speed Test RPMs 2625
Standard.........Current Reading
HC- 220.................198
CO-1.20.................1.14
CO2-......................13.1
O2-........................1.2
Dilution->6.0............14.22

Low Speed Test RPMs 1101
Standard..........Current Reading
HC- 220..................663......FAIL
CO-1.20.................1.59......FAIL
CO2-......................11.1
O2-........................3.6
Dilution->6.0............12.69

Crap it made it twice as bad as it had been. Ok so I found out high-octane fuel is not the right way to get less HC.
So I Seafoam intake again, Seafoam fuel, cleaned body grounds, cleaned battery connections, bumped the idle back down, richened air/fuel mix back, and filled it up with 87 octane.
Next morning I drove 10 miles on the highway and went back to retest and:
Here are the numbers:
High Speed Test RPMs 2573
Standard..........Current Reading
HC- 220.................162
CO-1.20.................1.38.....FAIL
CO2-.....................12.8
O2-.......................1.4
Dilution->6.0...........14.2

Low Speed Test RPMs 808
Standard.........Current Reading
HC- 220 ..............1008.....FAIL
CO-1.20................4.19....FAIL
CO2-....................9.0
O2-......................5.0
Dilution->6.0 ........13.15
Now I’m really trippin’ what do I do now. After much reading and testing. I replaced weak coil with Accel Super Stock, new Bosch plugs, replaced PVC valve, but couldn’t set timing! Found out why jumping T and E1 wasn’t idling it down. Got codes that never showed up and replaced a bad TPS, replaced bad 02 sensor, cleaned throttle body, cleaned plenum, cleared codes, set timing and off I go thinking the TPS or O2 was the problem all along. But on my warm up drive the exhaust smells weird, different than it ever has. Now I'm thinkin' replace cat if it fails again?
I go back this morning and as he was starting the test it started loping so he couldn't even keep it steady enough for the test to run. STOP EVERYTHING! Great now I can't even get a test or find out what the numbers are because of where this story started.
I what I know and can’t find much. So I removed the throttle body again, tested the TPS again, readjusted it again. Before putting it back on I saw the wire for coolant temp sender was broken. I figured out which one it was and replaced the THW, and put throttle body back on. Same thing motor lopes between 1600 and 2000 RPMs with slight throttle applied.
I figured I would check at the ECU to see if the right voltages were getting there but before I got to that test I found out…
Voltage test at ECU:
E1-Batt= 13.1v
E1-+B= 0v & +B – body ground = 0v
E1-+B1= 13.1v
Don’t +B & +B1 share a common wire to a point? This tells me +B has a break in it somewhere after it splits with +B1 correct?
What’s my next move? Electrical is my weakest skill when it comes right down to it I SUCK!
I’m not sure how to proceed with getting’ this baby road worthy again. I just keep finding issues everywhere I look to fix a problem.
Any help, advise or info would be great!

norcal93

That seafoam breaks up the carbon deposits in your intake, but it also sends it down through the exhaust. All that crap you saw come out of the exhaust was carbon buildup that made it PAST the cat, imagine all the buildup that didn't make it past. Its possible that it has built up in the cat and is burning off and thats why your tests are getting worse each time. Don't get me wrong, seafoam works to clean, but it is by no means a end all cure all treatment. Was the seafoam still in the tank when you had it tested?

If the tps test out ok per factory spec, i'd run it.

Sounds like you have really exhausted all your resources, i've been there and its frustrating.

meswoleshane

My 4runner does this too. I live in Mississippi and we don't have emissions laws here thankfully. I just switch gears so the rpm changes and keep on going... I have always just thought the TPS was off some. It likely has a burnt or worn spot somewhere in its rotation that the FSM test doesn't pick up.

1sennafan

Thanks Guys
"a burnt or worn spot" makes perfect sense now that you said it. So am I right the TPS is what activates the fuel cut RPM? Because I cant just run it, I cant get it inspected the way it is. I use to know a "guy" but I no longer have a friend in that department if ya know what i mean.
No Seafoam was not in tank when last tested, it was a full tank of Shell 84 octane. "built up in the cat and is burning off" would account for the smell also maybe?

1sennafan

1-1/2 hours and $85 bucks later its defiantly not the TPS! Brand spankin’ new one and it still does the lope thing.
The only thing changed before it started this was the O2 sensor I guess Ill look into that next. Someone has to have fixed this problem before.
I have a ECU out of my 87 4runner but its says 22r not 22re but the 87 was EFI. Could it hurt to try the older ECU?

meswoleshane

Man that sucks. I've tried switching TPS sensors and ECU's (I've had several of these trucks.) Did the same thing with all of them. I figured all the TPS sensors wore worn similar because where the engine looped at was average rpm range that would be used for most driving, so 20+ years of rotating did the same thing to both of the sensors I had on hand... The FSM actually calls for trying another ECU in some of the tests. Keep us updated on this I'd like to know whats going on.

meswoleshane

I also tried switching the AFM and it did the same thing. The only thing I didn't change is the O2 sensor. But, when I unplugged it the engine still looped...

meswoleshane

I don't have a converter and mine does the same thing...

22mr2

check to make sure you have vacuum to your egr, had a similar problem, metal line leading to egr was plugged

usmc-lazer

Got to love electronics some times.

1sennafan

OK after doing the voltage at ECU tests everything looks good but:
Igt-E1 calls for 0.7-1.0 I have 1.3
Vs-E2 Open calls for 0.2-0.5 I have 7.1
Vs-E2 Idling calls for 2.3-2.8 I have 6.2
Any ideas why or how to fix?

1sennafan

OK got voltages fixed, airflow meter was bad. EGR working as it should. AS working as it should. Reset air gap to specs. Tested both VSV’s working as they should. Cold start time switch tested good. New temp sender so it should be good.
Old O2 sensor changes at what RPM this issue starts but test bad.
Never did solve surge problem but I did adjust TPS enough to stay above 2200 RPMs and pass inspection

1sennafan

So this is what a factory spec EFI & Emissions, 89 4runner is supposed to run like?
Well it does run better but it sure stinks at times.
Ive had to change my driving style already to more RPMs in 1st – 3rd due to the “fuel cut RPM” thing at anything under 2000. Here are the numbers, however 210,820 is really more like 350 or 375,000.
992 RPMs reads 800 on my tach