Topic: 88 22re w/ low miles - fuel problems

[IVrunner]

I am interested in getting an 88 4runner with a 105K original mile 22re with a 5 speed.  It has spent most of its life in florida, so it its completely rust free.  it was originally an auto, but due to problems it sat for a long time (as you can see by the amount of miles).

The following is what i have found form the current owner.  i want to know if the truck is worth buying because it seems like an easy fix, but then again i don't know what i'm getting myself into.

Quoting the current owner:  "There is an issue with the electronic fuel injection sensor system. The truck will start, and idle, with a little playing with the timing and idle speed, but when you apply quick throttle, it runs really rich (too much fuel) and stalls." 

does anyone know what it could be?  is it a bad sensor?  timing way off?  air/fuel ration (don't believe it to be adjusted from stock)?  bad injectors?

Please let me know your thoughts.  Thanks in advance.

[IVrunner [OP]]

more info from the current owner:  "the following have been replaced: the fuel pump/filter, plugs, cap, rotor, battery, alternator.  I tried to adjust the mass air flow sensor, timing,and idle speed, still boggs down with fuel.  it doesnt smoke, but the exhaust does smell rich when i can get it started"

[IVrunner [OP]]

anyone have any thoughts?

[93tonkatoy]

The fuel system should hold pressure after shutting the engine off. Crank the engine over a couple times (it doesn't have to start) and turn the key back off. Then loosen the fuel fitting to the cold start injector (on the site of the intake plenum). If fuel SQUIRTS out then it is okay (and skip to the following paragraph). If it does not, then it (or one of the main injectors) may be stuck open (drowning your intake with fuel). The extra fuel will not burn, causing the "rich" smell in the exhaust, and also will wash past the rings, thinning your oil. You should be able to tell which injector (if a main injector is sticking open) is the problem by inspecting the spark plugs. The blackest plug will be in the cylinder connected to the offending injector. If they are ALL black pretty evenly, then the cold start injector will most likely be the bad one. If you locate 1 or more that are staying open, check both wires in that plug for a ground. Use a test light from the + battery terminal to the pin in the harness plug. If EITHER of the wires in that plug are grounded with the key off, then you have a short in the wiring harness somewhere. On a 22r-e the injectors get a constant +12 volts, and the grounds are switched by the computer. If the wiring checks okay, then you may need to have the injectors tested and cleaned. There are companies you can ship your injectors to who will clean and refresh your injectors for a good price, and some have very quick turn-around times.

With the fuel system holding pressure, that means all of the injectors are closing properly. When it does crank for the first time, does the idle start out high for a couple minutes? then slowly drop down to normal? What does it do if you unplug the connector from the cold start injector? If you do not get a high idle from a cold start, try adjusting the idle screw out, and see if it will stay running better. If so, I'd do a very thourough inspection of the auxiliary air valve (part of the bottom of the throttle body - held on by 4 phillips screws). With a cold idle the valve should be open, allowing additional air to bypass the throttle plate. As the coolant starts warming up (flowing around the bulb in the valve) the valve closes, cutting the extra air off.

Another possibility is that the EGR valve itself is not closing properly (vacuum system okay, but the valve it all controls may be carboned up, and stuck open). A quick throttle burst would force extra oxygen depleted exhaust freely into the intake, and cause the mixture to get even richer. The connection on the rear of the intake plenum can be temporarily blocked off to eliminate or pinpoint this possibility.

If the MAF sensor has been adjusted, I would try to find and borrow one that you know works, and swap it in. There were a couple of different configurations, and they will not swap out. Depending on what it does then, you will know if that is the problem.

Just some things off the top of my head. hope you get it going.

[IVrunner [OP]]

Thanks so much 92tonkatoy.  I would jump on these to diagnose the problem right away, but i do not have the truck in front of me nor is it mine to do so.  I could help him out to diagnose the problem, but i dont want him to fix it cheap and change his mind about selling it.

The main question i have now is - out of the options you listed off the top of your head, what is the highest cost it would be to fix the problem (assuming i am doing the work)??  i understand it would be an estimate, but i wanna know if its worth it to buy - the guy is asking $1000.  its very clean, with newer tacoma wheels, nice tires, original paint, 3" BL, etc.  problems include AC that needs work, windows need a master switch, cracked sunroof, and fuel problems of course.  what do you guys think...is it worth it??

[93tonkatoy]

First, for $1k, don't worry about the problems. BUY IT! I would estimate that the most expensive part to replace (fuel problem wise) would be if the AFM were bad (speaking retail prices). If you need the injectors serviced, less than $100 to have all 5 done (that includes the cold start injector). If you need to replace the bypass valve on the throttle body, I heard a retail price of around $130. With those prices in mind, keep your eyes on the for sale section here. people are always buying parts trucks and parting stuff out, usually at good prices. With a little troubleshooting and thought, you could have the truck running for around $200, then fix all the other things as you get to them.

[IVrunner [OP]]

Thats what i was hoping to hear.  Thanks again.

If i do get it I will update this thread on what i find out