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Discussion Starter #1
Hello everyone, hoping someone can direct me in the right direction here. here is the back storry
Bought this rav4 from someone that blew the head gasket so i had never driven or started the rav till after I completed the job.
Current issues i am having is that the fuel cuts off at about 4500 rpm but its not like its hitting the redline witch is at 6k if you push it hard to try and get over that 4500 mark all fuel cuts off and stalls, i would have to pull over turn key off and back on and it starts right up?
things i have replaced to try and remedy this issue are
Plugs (twice)
Wires
Fuel Filter
Cleaned out the Iacv (it was sticking)
as far as i can tell all vacuum hoses are connected and working right
other than the 4500 rpm issue seems to run fine
from time to time I get a Check engine light P0450 I don't think that is causing this issue but thoughts?

Thanks in advance for any and all help!
 

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Discussion Starter #3
I will get a new gas cap today but I don?t think that?s the part of why the fuel cuts off at about 4500rpm.
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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For the stalling, if there are no other codes then I would suspect a failing fuel pump. Test the fuel pressure and output.

For the P0450 code see https://www.yourmechanic.com/article/p0450-obd-ii-trouble-code-evaporative-emission-control-system-pressure-sensor-malfunction-by-valerie-johnston

It could also be a vacuum leak, I cannot stress enough about replacing all those old hard, brittle, and cracked vacuum lines, because they will cause a parade of engine codes and you'll buy a lot of parts you don't need. See http://www.rav4world.com/forums/94-4-1-d-i-y-modifications/255961-vacuum-line-replacement-high-temp-silicone-lines.html
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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I don't know that much about fuel trim, I will have to bone up on it. But I do know that you need to measure it for at least 30 seconds at three different engine speeds: idle, 1,500 rpm and 2,500 rpm, being your trouble is at 45000 rpm I would measure it there as well. Just because the fuel pump is keeping up at idle doesn't mean it is doing well at higher RPMs.
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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Okay here is some info from Fuel trim: How it works and how to make it work for you - Automotive Service Professional

Why are the numbers low?

If LTFT or total fuel trim is more than 10% negative, the PCM thinks the air/fuel ratio is too rich, so it is leaning out the mixture calculation to return STFT control to the correct range. This presents three possibilities:

Not enough air is reaching the combustion chambers.
More than the commanded amount of fuel is reaching the combustion chambers.
One or more sensors is reporting incorrectly.
One thing that restricts airflow into the cylinders is a damaged catalytic converter that causes high exhaust back pressure. At idle this can drive fuel trims in opposite directions, producing a positive STFT and negative LTFT. You can see signs of high exhaust back pressure on a scan tool; calculated load will be low at wide-open throttle (WOT) and fuel trims will trend negative as engine speed increases.

The most obvious source of excess fuel is a leaking injector, especially at idle. In this case, STFT will be low but increase with engine speed as the extra fuel represents less of the total fuel requirement. Excessive crankcase vapors or a flooded EVAP canister can also mimic excess fuel, especially at idle. If the oil hasn’t been changed in a long time, especially in an older engine with a bit of blow-by, fuel in the oil can drive total fuel trim negative. Often simply changing the oil will demonstrate this condition by returning the fuel trim numbers to normal.
 

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Discussion Starter #9
Thank you very much!

Ok well the vapor code went away
but still have the cutting out at 4500
i will find a way to test fuel pressure
abt other suggestions let me know :)
 

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Discussion Starter #10
Ok got everything running perfect NO CODES passes smog runs GREAT .... BUT Still have the cutting out at 4200-4600rpm WHYYYYYYYY?????
Things I replaced
TPS
IACV
Fuel filter
Fuel pressure regulator
Fuel Injector damper
Fuel Rail
Fuel Injectors
got all the vacuums in correct spot
Took it to a mechanic and they said well WHY would you want to go over 4500 rpm in that thing anyways??? That's NOT THE POINT! the damn redline is like 6.2k I think WHY does it cut out as if its hitting red line at Aprox 4500 RPM?????
This is insane I have never had this hard of a time finding a issue.
I am completely lost on this one and will not accept THAT is normal!
 

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Discussion Starter #11
And Problem solved after tearing it all apart again and triple checking everything come to find out the Crank Position Sensor was bad but gave NO CODES! so irritating!
 
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