91 4runner acceleration problem
thebes
09-12-2006, 01:02 PM
Hello everyone, I am new to this thing....
I own a sr5 v6 toyota 4runner, took it out 4wheeling last weekend, had a blast and everything went smooth, actually better than expected, the truck performed awesome. However while driving it the next day I noticed I could not push the gas peddle too quickly, because it only caused the engine to bog out. At first I thought the 31 inch tires could be the culprit since they had not been on before the trip, but removing them did nothing. I have replaced the sparkplugs and air filter, and checked all the air induction pipes. The trucks run perfect in park, rpms climbing easily and steadily, but once put into gear I can not get more than 1200 rpm before the engine almost quites. The transmission, I believe is fine, since I can 'coast' down hill and have it shift through every gear. Anyway there is my story and problem because I am not sure what to do next.......hoping it is not an electronic problem. Any ideas out there?????
-Devin
I own a sr5 v6 toyota 4runner, took it out 4wheeling last weekend, had a blast and everything went smooth, actually better than expected, the truck performed awesome. However while driving it the next day I noticed I could not push the gas peddle too quickly, because it only caused the engine to bog out. At first I thought the 31 inch tires could be the culprit since they had not been on before the trip, but removing them did nothing. I have replaced the sparkplugs and air filter, and checked all the air induction pipes. The trucks run perfect in park, rpms climbing easily and steadily, but once put into gear I can not get more than 1200 rpm before the engine almost quites. The transmission, I believe is fine, since I can 'coast' down hill and have it shift through every gear. Anyway there is my story and problem because I am not sure what to do next.......hoping it is not an electronic problem. Any ideas out there?????
-Devin
Brian R.
09-12-2006, 03:57 PM
Welcome to the AF!
Check to see if you damaged your pipes, muffler or cat. converter. If any of these are restricted, you will see the effect you are observing.
Check to see if you damaged your pipes, muffler or cat. converter. If any of these are restricted, you will see the effect you are observing.
thebes
09-13-2006, 07:00 AM
Thanks for the tip Brian and I will go home after work today and inspect my exhaut system.....but if the pipes were restricted then wouldn't I see this same effect while the vehicle was out of gear. I mean the pipes would restrict the flow no matter what position my tranny was in, since so long as my engine is running the exhaust from the burning gas has to leave through those pipes.
Perhaps you know something I don't.
Thanks,
Devin.
Perhaps you know something I don't.
Thanks,
Devin.
Brian R.
09-13-2006, 09:59 AM
When you're in gear and the engine is loaded, there is alot more gas being burned to power the truck or just turn the torque converter if you are stopped than when you are idling or just turning your crankshaft with no load. More gas being burned makes alot more exhaust gases that have to pass through your exhaust system.
Even if your cat. converter looks ok, it is a known problem if the catalyst bed gets damaged and restricts flow. All the catalyst can get bunched up and plug up the exhaust passage in the cat. converter.
Just guessing though. You may have a much more complex problem than that, but this is the first and easiest thing to check out. One symptom of this problem is your exhaust will sound different under load than it used to, like a more constant blowing sound than the normal blub blub blub.
Even if your cat. converter looks ok, it is a known problem if the catalyst bed gets damaged and restricts flow. All the catalyst can get bunched up and plug up the exhaust passage in the cat. converter.
Just guessing though. You may have a much more complex problem than that, but this is the first and easiest thing to check out. One symptom of this problem is your exhaust will sound different under load than it used to, like a more constant blowing sound than the normal blub blub blub.
thebes
09-13-2006, 12:47 PM
Thanks for clarifying that. Makes sense, and I will get back to you tomorrow.
-DLB
-DLB
thebes
09-14-2006, 12:30 PM
No exhaust restrictions anywhere. I am going to try a new fuel filter to night, but thank very much for offering me some advice.
-DLB
p.s. -I will let you know if anything changes.
-DLB
p.s. -I will let you know if anything changes.
Brian R.
09-14-2006, 12:56 PM
Check your
VAF Meter and circuit
Throttle position sensor and circuit
Fuel pressure regulator
Injectors
EGR system
If you have any gas smell in the engine compartment, check your fuel line pulse damper near the firewall for leaks.
There is a '93 pick-up/4Runner manual in the sticky post at the top of this forum
VAF Meter and circuit
Throttle position sensor and circuit
Fuel pressure regulator
Injectors
EGR system
If you have any gas smell in the engine compartment, check your fuel line pulse damper near the firewall for leaks.
There is a '93 pick-up/4Runner manual in the sticky post at the top of this forum
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