Fugen183

So i got an 88 4runner "bonnie" from a guy, shes a 22re engine with 5spd manual.When i test drove i could get to 45mph through all 5 gears but it would bog halfway through each gear. I checked lines,hose, and gaskets for air and vacuum leaks and found none. Has new distributor rotor,cap,plugs,wires,air filter,fuel filter,fuel pump,and resealed rocker arm cover. Timing is at 5°btdc and advance works. Ohm'd the MAF sensor compared to my haynes manual and it was bad so i replaced it. Now i cant get past 15mph before it bogs like i let go of the gas. Ohm'd the tps and it was bad as well so i replaced and properly adjusted that idle sounds better but doesnt run better. Igniter coil checked fine as did spark wire firing order. I need to grab a gapping tool and go check my plug gaps though i doubt that will fix it. Ive test just about everything that doesnt involve tearing down the motor. Kinda at a loss atm any other suggestions?

Co_94_PU

iTrader: (-1)

Fuel supply... Volume and pressure checks

Boostincx

Knock sensor retarding timing? Mine's doing that with a code 52. It's a known issue and easier to remedy on the 22r than the 3vze from what ive read. Are you showing any codes?

Fugen183

Ill have to jump the diag terminals and count the flashes monday since i wont be home till 7 the next 4 days of work.

Fugen183

output side of fuel filter has alot of pressure with the new fuel pump however ive no gages to properly read fuel pressures atm

wallytoo

iTrader: (1)

a "lot" is relative. the system needs between 28 and 40 psi depending upon conditions to run correctly. meanwhile, 18 to 25 psi will seem like a "lot", but won't be enough for the engine to run well under most conditions, and will run poorly or not at all most of the time. verify pressure, then go from there.

wally

atcfixer

iTrader: (1)

Yea I'd agree it sounds like a fuel delivery/pressure issue. I did have a grand am before that would pop and miss slightly at high load and it ended up being a bad spark plug that I replaced the day before.

Fugen183

Ok so checked codes this morning and none. I removed the cushion to the rear passenger seat and pulled my fuel pump. Vacuumed 5gals of gas and a bunch of rust hidden in it. Refilled with 7 gal and a can of seafoam got her to 65 in 5th and half way through the test drive she began to bog again. Im about to head and and grab a fuel filter to replace the one thats on there and let that seaform idle its way through the engine. Progress! Wifes crv had a similar issue shouldve looked there first but oh well live and learn.

atcfixer

iTrader: (1)

Did you replace the strainer on the pump? They are cheap enough to just buy new.

Depending how bad the rust was, might be good preventive maintenance to just replace the whole tank.

Fugen183

No but i did clean it thoroughly with the ever lovely flamable wasp killer known as brake cleaner and let that all dry off before reinstalling. Rust wasnt bad enough to compromise the integrity of the tank or warrant its replacement

Fugen183

Started looking other directions too since i had time. FPR works. EGR vacuum modulator: filter dirty feed hose....completely packed with carbon...used a pick,screw driver, and my trucks brushguard(hitting the hose on it) to break the carbon loose. Didnt fix it. Grabbed a hand pump and pulled vacuum on the EGR at 5psi vacuum on the EGR engine died. EGR is bad. New one arrives in the morning ill test and update again.

Boostincx

I know you said you adjusted your tps, but i am battling the same issue right now with my truck (94 ext cab 3.0 v6 M/T). I got my new knock sensor and wire to remedy the code 52, relocated it to the engine lift hook by welding a nut onto it near the top so the sensor sits straight up and down like it does when in the block. No more code 52 but I was still getting the bogging and bucking almost as if its a rev limiter between 1500-2000 rpm. Well this morning i decided to mess with it some more, turned my idle screw all the way down until it almost died, then turned it back up about 1 full turn maybe 1 1/4 turn at most. Then i started moving the TPS sensor until the idle started coming up, VERY SLIGHTLY turned it back and tightened her down, seems to be about right in the middle of my adjustment range on the TPS (i installed the allen bolts in place of the phillips to make it easier). All of the sudden i cant get it to hit the rev limit/fuel cut/whatever... or buck and kick like it was before. Its not even throwing the TPS sensor code 41 any longer. I'm assuming i have a dead spot in my TPS or it was just not adjusted correctly the first time i did it with the feeler gauges. I plan to pick up a brand new OEM Toyota TPS sensor this week its $108 piece of mind, the one i have on now was a "good used" one off of Ebay. I'll keep you posted on my outcome, also interested in the EGR your doing as im not 100% sure how it all works.

Fugen183

Ive exhuasted just about everything i could think of until i landed at the EGR but the tps issue i had on an 85 4runner that gave dad and i troubles for weeks. Good idea on the allen head screws vs the phillips...i removed the housing over the thermostat just to have room. The EGR (exhaust gas recirculation) works by opening the valve when the engine temp is past a certain threshold allowing exhaust back into the cylinders further burning out NoX and reducing the temp required for combustion. Once the temp drops the EGR closes. It can allow carbom build up and clog ports or hoses sometimes too and ive seen it cripple alot of deere machines ive worked on. Ill pick up my new EGR valve in the morning and install it so see if it solves my issue and let you know.

Fugen183

EGR helped but didnt solve my issue. Started checking the distributor and found my signal generator readin 185ohms (140-180 range.) as it cooled it dropped to 179.5 ohms. Replaced it and she sounds much better but it actually made the problem worse (just like the new MAF) ove had alot of issues with electrical devices....perhaps somethings up with the ECU but im not getting any random codes or spazzing behavior from it. My other thought is checking injectors. Ill my ecu and ohm my injectors monday.

atcfixer

iTrader: (1)

Did you get to change out your fuel filter yet? If not, I'd say wait till that's done first before trying to dig deeper into a problem that might be fixed by that. If the fuel filter doesn't help, it might be some fine junk got past the filter and has the injectors clogged up some. Wouldn't be a bad idea to flush the fuel lines while changing the filter (atleast up to the filter).

I wouldn't have thought the 185 (5 ohms over spec) would cause any problems, did you replace the whole distributor or something, maybe it was cap/rotor that made the difference, vacuum advancement etc? Talking about that, I don't recall details about plug wires or plugs? If they are old it might be a good idea to swap them out. That's one of the first things I do when I buy something to drive so I know when it was done (unless they look newish and are a good brand). I'd stick with NGK or Denso for the ignition parts.

While you're reading things, wouldn't hurt to check your coil out, but I think they generally work or don't work, and partly failed I'd think there would be more issues on the bottom end with high load rather than higher rpm.

If all checks out well and the truck still bogs, maybe post a video on youtube? Some times someone experenced with your problem can identify it if they hear it rather than try to read it typed out.

Fugen183

Fuel pump and filter are brand new also cleaned out the gas tank and been running seafoam to help clean the system. New ngk plugs also new cap, rotor, and wires. The signal generator was 5ohms over slightly warm didnt get to operating temp so it wouldve been higher but it made a signifgant difference when replaced. Havent replaced the distributor itself though it has no excessively play in the shaft either. Also checked timing its at 5°btdc and advance works although its not a vacuum advance or if it is its not part of my distributor like the book shows for carb running trucks goven the year advance might be part of the ECU programming
​​​​​​. I already check my coil and it matched specs in the manual.

Boostincx

What about your O2 sensor? Or your catyletic converter? Just throwing out ideas...

Fugen183

Checked cat since i just had an issue with the one on my wifes crv and removing it didnt help but i could try it again for grins and giggles. O2 sensor doesnt seem like it would be it given that i have no codes for it but its certainly worth the 2 seconds it takes to check it.

Co_94_PU

iTrader: (-1)

Can you ease through the rpm range that's giving the trouble? This would indicate valve timing issues due to the chain stretching as the cam "catches up" to the crank speed.

Did you clean up the coolant temp sensor (body and housing/ground) when you had the thermostat housing off. If it has poor ground it will falsely indicate a cold engine and trigger the warm up enrichment.

You changed out a faulty air meter and got a negative result to performance as well a failing TPS. These two items are making the ECU command more fuel. You haven't done the fuel pressure and volume checks but got a better result temporarily when you changed the pump and cleaned up the tank, this leads to possibly plugged injectors (rust and or gel) but could also be over fueling. A check of the VF signal might be a good use of time. It can run continuously rich or lean and not throw an error code as long as it doesn't reach the maximum adjustment.

It could be knocking or reading a false knock and retarding ignition timing. You'll need to monitor the ignition signal under load. Since most of us don't have a rolling dyno you'll have to rig up a camera and timing light to record during a road test. I'm not sure if just putting it up on jack stands will provide enough load, but might be worth a try first. In either case remember safety first, have a friend on hand, do not the stand in front of it or inline with the belts and fan, ect..

Fugen183

Ive tried to ease it through the rpm range but it doesnt work but i can go back and check the valve clearnces and such. Talking with my dad about it (he had an 85 4runner) he said it should have hydraulic lifters that self adjust. Do you know this to be true? ˟˟˟˟ adjustment could be the issue all together.

When i had the housing off i did inspect the thermostate and such making sure they were clean before rejoining but didnt do indepth checks.

Ive got the fuel gage i just have to find fittings that will mate with my trucks fittings. As for clogged injectors ive added and let seafoam run through in hopes of cleaning them but so far no good and ive yet to dedicate myself to tearing down the intake side.

I can get through first easy so i dont think loading it down while on stands will do it as for rigging the camera and timing light...well thatll be fun ill remove the hood for that.