87 4Runner Rough Idle/Misfire issues
 

So started troubleshooting this a couple weeks ago, but I haven't been able to figure this out. Here's the symptoms I had leading up to the current issue:

Warmed vehicle up and drove about 15 minutes down the road, everything was good. Turned the vehicle off and let it sit for a couple hours. After turning it back on it seemed to drive fine, as it warmed up I started getting loss of power above 3k RPM, putting down the accelerator would cause it to choke and stall out. By the time I was pulling onto my street it would stall out if I let it idle. Basically had to keep it around 2k RPM at all times otherwise it would drop too low and die.

I was able to start doing some testing a couple days later with a friend that knows a bit more about the engines:

1. Replaced distributor cap, rotor and ignition coil wire as there was carbon buildup, and corrosion/debris in the cap ignition coil wire connector. No change..
2. Compression - all ~150
2. Vacuum tested, didn't see any problems.
3. Light tested all 4 ignition lines, all spark, with no irregularity.
4. Checked timing with a Timing Light. Looks good.
5. Replaced Fuel Filter. No difference.
6. Tested resistance on MAF - all looks within spec.
7. Coolant was low, filled it up, no difference in operation. The radiator is leaking slowly from the weld points, but it's done that since i owned it, and the reservoir will never completely empty.

Current operation: Engine will fire up just fine, but misses. There's a smell of fuel, and when it runs rough it doesn't seem like it's missing any specific cylinder. I can gas it to ~1500 RPM and it evens out, with an occasional miss. 2000RPM+ it runs perfectly fine, no misses. I was able to go over 3k RPM without the engine stalling out, so I'm not sure if that issue only came about after the engine had heated up.

I'm at a bit of a loss on where to go from here, TPS? Ignition Coil?

Any help appreciated thanks.

Did some more checks today.

Inspected cold start injector. It is extremely dirty. Resistance is 4.6 ohms, seems high.
Vehicle still starts and smells like gasoline in the engine compartment with cold start injector disconnected. I would have thought the vehicle would not start if cold start injector was disconnected.

Ignition coil resistance is 1.8 ohms, this looked 3-4x as high as it should be based on the '93 FSM spec. secondary resistance was 13.6k ohms. which was in-spec.

Coolant temp sensor resistance was ~1800 ohms. I believe that's correct based on http://www.4crawler.com/4x4/CheapTri...ne_Pix/21.html

TPS resistances at closed/open checked out, but I don't have gaps for the correct mm to do the full test.

I'm going to replace the coil and go from there.

Hey man I was having very similar issues as you. For me it ended up being the ect sensor next to the cold start injector. I've been running my truck for over a month now without the cold start injector plugged in sometimes it was the only way to get the truck started up again after stalling before I fixed the ect issue. Ran great for a week...now more problems.

Good luck. :safari:

ah I guess the correct test is to pull it out and put it in cold water and verify that the resistance changes properly when it goes cold/hot. I'll try that. Also I noticed the connector housing to the ECT is busted.

Thanks montana.

Hey guys, I just got an 87 4runner and have very similar symptoms. This is an old thread I realize but was curious how your fixes turned out. Any further info that anyone has would be very helpful. Also if there was a re-direct I'm not catching I'd grateful for anyone's direction.

Thanks

Need help please
 

Hello I have 1987 4runner 22re it was running fine last week haven't drove it in a week. Now went to start it. It started fine then immediately started to run rough very rich sounds like it's running on less than 4 cylinders it has power there is a little gray smoke coming out. I checked the codes and code 6 and 12 pop up one of the codes might be old never clear them before they and check engine came on once but it went away so I never check it

haven't had time to fix much I've replaced the O2 sensor since I last posted, and disconnected the battery so that everything could reset, but no improvement. Probably going to take it into a shop soon and just have someone else work on it as I really need it running.

Sounds exactly like TPS symptoms (one of the most common and free to fix problems).

You definitely need a feeler gauge to check / adjust it properly. It's a worthwhile tool to have- you can also adjust your valves when needed.

TPS adjust with Reman AFM
 

Thx for the response. Just got an A1Cardone AFM reman (one of the circuits on the previous AFM tested bad). Ohms on the reman all read in proper ranges. SOOO... time to tackle TPS. I've got the hex screw mods on standby, gotta go get a feeler gauge set but was wondering which range is best. Seems that maybe a set of like 10 or 12 that cover the ranges i need would be practical, not sure I'll ever need all 32 feelers if i get the jumbo set. ...but would that be best to have or just overkill? My TPS is def not set correctly, it was loose when i got it and i checked the idle stop screw other day, not even making contact. LOL. Sorry so much info... last question. My TPS did spec fine on ohms test BUT if i do need to replace it, will an o'reilly BWG aftermarket do well? I saw one at the store and it looked well made (seems like a straight forward and simple sensor).

Thanks again. Cheers

Took my 4runner into a mechanic a few months back, the issue ended up being the intake was pulling away from the head causing a vacuum leak. This caused it to rev up oddly at random, and was also causing the fuel smell in the engine compartment. After a new gasket and bolts (They mentioned it was actually missing a couple) everything is back working as normal.

Mine idles irregularly but I'm thinking it's the timing chain guides being shot. It sounds like the chain is ticking a bit. I replaced all my vac lines and didn't get any surges when i speayed carb cleaner around to test. Tps, replaced as well.

That is a legit mechanic! How much did they charge?

i had a similar issue and did almost everything you did. My problem was t solved until I changed the Tempe Sensor. It was sending signal as if it was cold and that’s what was causing the issues. I also changed the EFI relay. No more issues.

[QUOTE = Sleaker; 52308409] Llevé a mi 4runner a un mecánico hace unos meses, el problema terminó siendo que la entrada se alejaba de la cabeza y causaba una fuga de vacío. Esto hizo que acelerara de manera extraña al azar, y también estaba causando el olor a combustible en el compartimiento del motor. Después de una nueva junta y pernos (mencionaron que en realidad faltaban un par), todo volvió a funcionar con normalidad. [/ QUOTE]
No entendí, como lo resolviste?
el problema terminó siendo que la entrada se alejaba de la cabeza???

Perdida de potencia
 

Continuando con los síntomas que antes mencionaron, mi camioneta (Toyota pick up 1993 4wd) tiene problemas en el realenti, cuando la enciendo trabaja con normalidad, pero después de 15minutos de uso, al tener el vehículo en marcha mínima se alteran las rpm, suben y bajan constantemente, también pierde mucha potencia, ya que exige que mi pie pise pedal a fondo para avanzar. Al parar y mantener el freno también se alteran las rpm y suben un poco. (Ya probé que no haya perdidas de vacio y también verifique el Booster)
Estoy un poco confundido, aún no se por donde empezar, ya estuve
​​​​​en varios talleres y nadie me ha dado solución. Espero alguien arrojé algo de luz. De antemano gracias 😓.

Little known secret about 22r and re’s
 

[QUOTE=Sleaker;52280611]So started troubleshooting this a couple weeks ago, but I haven't been able to figure this out. Here's the symptoms I had leading up to the current issue:

Warmed vehicle up and drove about 15 minutes down the road, everything was good. Turned the vehicle off and let it sit for a couple hours. After turning it back on it seemed to drive fine, as it warmed up I started getting loss of power above 3k RPM, putting down the accelerator would cause it to choke and stall out. By the time I was pulling onto my street it would stall out if I let it idle. Basically had to keep it around 2k RPM at all times otherwise it would drop too low and die.

I was able to start doing some testing a couple days later with a friend that knows a bit more about the engines:

1. Replaced distributor cap, rotor and ignition coil wire as there was carbon buildup, and corrosion/debris in the cap ignition coil wire connector. No change..
2. Compression - all ~150
2. Vacuum tested, didn't see any problems.
3. Light tested all 4 ignition lines, all spark, with no irregularity.
4. Checked timing with a Timing Light. Looks good.
5. Replaced Fuel Filter. No difference.
6. Tested resistance on MAF - all looks within spec.
7. Coolant was low, filled it up, no difference in operation. The radiator is leaking slowly from the weld points, but it's done that since i owned it, and the reservoir will never completely empty.

Current operation: Engine will fire up just fine, but misses. There's a smell of fuel, and when it runs rough it doesn't seem like it's missing any specific cylinder. I can gas it to ~1500 RPM and it evens out, with an occasional miss. 2000RPM+ it runs perfectly fine, no misses. I was able to go over 3k RPM without the engine stalling out, so I'm not sure if that issue only came about after the engine had heated up.

I'm at a bit of a loss on where to go from here, TPS? Ignition Coil?

Any help appreciated

Little known secret about 22r and re’s.
There is an emissions module located on the drivers kick panel (on pickups). Over time they develop hairline cracks around the connector pins on the circuit board and cause sporadic connection problems. You will need a strong magnifying glass or jeweler lope to see the cracks. A reflow on the solder on each pin will solve the problem

Little known secret about 22r and re’s
 

I may have screwed up my first try at posting. Trying again.


Little known secret about 22r and re’s up to 1988
There is an emissions module located on the drivers kick panel (on pickups). Over time they develop hairline cracks around the connector pins on the circuit board and this causes sporadic connection problems including rough idle. You will need a strong magnifying glass or jeweler lope to see the cracks. A reflow on the solder on each connector pin will solve the rough idle problem in many cases.

Secreto de 22r
 

[QUOTE = Rail Bert; 52449580] Es posible que haya arruinado mi primer intento de publicación. Intentando otra vez.


Secreto poco conocido sobre 22r y re's.
Hay un módulo de emisiones ubicado en el panel de protección del conductor (en las camionetas). Con el tiempo, desarrollan pequeñas grietas alrededor de los pines del conector en la placa de circuito y esto causa problemas de conexión esporádicos, incluido un ralentí irregular. Necesitará una lupa fuerte o un joyero para ver las grietas. Un reflujo en la soldadura en cada pin del conector resolverá el problema de inactividad en muchos casos. [/ QUOTE]
Es un poco confusa la respuesta, podrias dar mas informacioncion.