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Discussion Starter #21
I put in a new crank shaft positioning sensor and the engine still dies


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Discussion Starter #22
Haha sorry about leaving that part out, so the mass air flow sensor can be messed up?


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Research the diagnostic procedures for fuel, air, and spark. Purchase a digital multimeter and back probing pins to test each of the associated sensors and compare to oem specification. Throwing parts at the car on a whim without testing the components first is going be very expensive.

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Discussion Starter #24
If the MAF sensor was bad wouldn’t the check engine light come on?


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If the MAF sensor was bad wouldn’t the check engine light come on?


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(I have not read this thread yet)


The MAF can in fact be messed up, or maybe should say not accurate, and not throw a code.
 

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Ok thanks


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I would attempt to just clean it first. Don't just go buy one.

I am running a MAF from a car that rolled lol. The MAF was DRENCHED in oil. I cleaned it real good and it tested fine after.

Get a can of MAF cleaner at the parts store. Use ONLY MAF Cleaner.

You can test the MAF with a scan tool. The FSM will give you the numbers you should see in certain conditions to confirm the sensor is within spec.
 

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Discussion Starter #28
I would attempt to just clean it first. Don't just go buy one.

I am running a MAF from a car that rolled lol. The MAF was DRENCHED in oil. I cleaned it real good and it tested fine after.

Get a can of MAF cleaner at the parts store. Use ONLY MAF Cleaner.

You can test the MAF with a scan tool. The FSM will give you the numbers you should see in certain conditions to confirm the sensor is within spec.
Ok i will try cleaning it. I dont have a scan tool


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I am mentioning this just so it is mentioned. It is not likely the problem. But someone with this problem could definitely end up seeing this thread searching their problem.


Your symptom could be something odd like the coolant temp sensor. If a car is fine in cold start but then has problems once it warms up it worth checking the temp sensor.


I am not saying it is your problem.
Just throwing out there that if a car won't run right once warmed up it can be because the temp sensor is faulty. ECU keeps running in warm up parameters even though temp is already up.


From what you have posted I don't initially suspect this.
Throwing it out there anyway.
 

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Ok i will try cleaning it. I dont have a scan tool


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Go ahead and clean it anyway.

You should order a OBD2 Bluetooth thingy. And get an app.
Handy to have.
Good as, often better than, a cheap scanner and usually cheaper.
Not as good as a quality shop scanner, but those cost a small fortune.
 

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I think sometimes you can see the mass air flow on some cheap $100 scanners. Its always in lb/min which you will probly have to convert to g/sec to match the given specs. I dont know the specs but I can probly look it up at work. And yeah after posting I was thinking that the cel should come on for anything related to maf.

It started happening as soon as you went through a big puddle? How soaked was the filter? Im assuming we are talking about a cold air intake?
 

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Discussion Starter #32
I think sometimes you can see the mass air flow on some cheap $100 scanners. Its always in lb/min which you will probly have to convert to g/sec to match the given specs. I dont know the specs but I can probly look it up at work. And yeah after posting I was thinking that the cel should come on for anything related to maf.

It started happening as soon as you went through a big puddle? How soaked was the filter? Im assuming we are talking about a cold air intake?
It is a cold air intake and the filter was pretty wet

it didn’t happen instantly. the rpms did kind of shake for a little bit when i accelerated in the rain. But the engine started dying like a day later


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i regret we couldn't get the wet maf across before you bought the crank sensor

as you see, going by simple discussion,
can lead to misleading conclusions

and while throwing parts at a car is a poor way of going about fixing it

most who ask this kind of question don't have the diagnostic tools to diagnose it themselves

and in actuality over 13 years
there are some pretty simple descriptions that alert us to common problems

for instance a clean car, suddenly won't go over 2500 rpm
locked in limp mode

most of us would scream MAF failure on reflex
lol

yours seems a bit more involved

def clean the maf with MAF cleaner and don't touch the sensor wire with your fingers
[leaves oil on the wire]

get a dongle and a car app
i use torque pro
useful for pulling codes and tracking vital components
screenshot_1502478377524 by Barry Belgard, on Flickr

btw
this is the reason dry airfilters may be better for our cars than oiled cotton ones.
if that oil on the filter is too much, oil may reach the maf and cause voltage fluctuations
 

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Discussion Starter #34
i regret we couldn't get the wet maf across before you bought the crank sensor

as you see, going by simple discussion,
can lead to misleading conclusions

and while throwing parts at a car is a poor way of going about fixing it

most who ask this kind of question don't have the diagnostic tools to diagnose it themselves

and in actuality over 13 years
there are some pretty simple descriptions that alert us to common problems

for instance a clean car, suddenly won't go over 2500 rpm
locked in limp mode

most of us would scream MAF failure on reflex
lol

yours seems a bit more involved

def clean the maf with MAF cleaner and don't touch the sensor wire with your fingers
[leaves oil on the wire]

get a dongle and a car app
i use torque pro
useful for pulling codes and tracking vital components
screenshot_1502478377524 by Barry Belgard, on Flickr

btw
this is the reason dry airfilters may be better for our cars than oiled cotton ones.
if that oil on the filter is too much, oil may reach the maf and cause voltage fluctuations
Dont worry about me buying the sensor . It was my fault for not adding enough detail.

Probably was going to need a new sensor anyway, i dont think it was ever replaced.

Im going to try to clean the MAF sensor and see what happens


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Discussion Starter #35
And what do i need for that app. Whats a dongle?, is it just the app or something else?


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Discussion Starter #37
Hey guys i fixed it! It was the MAF sensor.

I cleaned it but its still didn’t work so i ran some tests to see if it was bad and it was bad.

So I bought a new sensor and the car runs good now!

Thanks for all your guys help!


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Lol good! Be lucky it was only the maf that got damaged. Would hate to see rings seize or a rod bend with alot of water being sucked in.
 

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Yeah i was so afraid of water damage!


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Run a sri and you won't have this issue

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