okay so i had some issues with the cats
replaced them and the car ran like a dream
all the front cat biscuit had broken up and lodged in rear cat to cause blockage- suffocated the motor ---wouldn't run
so had towed - and the best exhaust shop in 100 miles got new aftermarket cats and put on ---$2000 later, sweet, fkn thing runs like a CHAMP, like a champ i say
UNTIL .... until i get home, 30 min away ....
....as i pull into driveway CEL goes on and stalled

ok so didn't get too concerned bc mechanic did say that i might want to clean or replace the MAF sensor ... he said it appears to be running ever so slightly lil rich, and maybe could be from the MAF---ok i go and check the codes.
damnit -few codes now
the first gang of codes were/are same codes as prior to replacing the cats. i was getting miss-fire codes on all cylinders.
my first effort was/did that i replaced the coils/wires/plugs= bc of the misfire codes. then that code came back and wouldn't run...ok so i deducted down to the cats AND the professional mechanic/guy even agreed with me --- so he/we changed the cats

BUT so the 2nd / last code was MAF p-0100
so instead of buying a 500$ MAF Sensor i tried cleaning it for 10$----everything ran great until it runs for a while=== almost as if like once under the hood get warm or something it dies.
so after work today i drove home and all was great and fine 20 min drive stopping/starting went to staples, etc etc
- but again as soon as i get home the car dies pulling up to mailbox to check mail.

so but it when dying today it didn't throw any codes- if CEL light not on, will my obbd reader maybe till see/get code??
I will check in few minutes

BUT so are we thinking that it is MAF?
he ran compression tests and all sorts of diag stuff and seemed to think this was ready to rook-n-roll

PLEASE looking for maybe someone that is savvy and stuff about possibilities ?? pls thx in advance

 

Sounds like it may be the crankshaft position sensor.

 

Yep, probably the crankshaft position sensor. To test the MAF simply unplug it and the engine will run on default mapping.

 

ok so i did do that
- i tried starting it with it disconnected. should i start it and then pull?

bc i couldnt start it with it disconnected

 

wouldnt that throw a code though?? idk - i know that you dont always get codes,
is there a like definitive way to test the CS sensor? perhaps

 

so okay
i started it----then popped hood disconnected MAF sensor thingy, and stalls/dies right down

means ??? bad maf or sensor or smth?

 

Sorry to hear it won't run with the MAF unplugged, that hasn't been my experience in the past. I've seen the opposite where it won't start or accelerate with a bad MAF, but once unplugged it will start and run. Have you checked the fuel pressure? That would be your next (should have been first) step.

 

sounds as tho i need find
fuel pressure test gauge

 

i will/need say that when cold, its fine, its after having driven for 46 min, maybe a little over zealous with the accelerator, but nothing in red, just passing and highway open fun stuff... but when hot it seems thats when it dies. i was almost thinking that the aftermarket cats arent processing the heat fast/well enough and its coming back up or off block under hood and causing electronics to not work properly

I will also add --- AND This is WEIRD
even since i got it back, and i manage to crawl it into driveway ---the alarm will sound for like 45min ish, every 10 min the alarm sounds,

after an hour it stop - iow...i leave keys in it the alarm will not sound.
but locked up and walk into house with keys...it sounds every 10 min ish.

alarm didnt sound today though
but car died by burger king today and that sucked. but sat for 30 min and then it ran fine

I think i am going to try to insulate the MAF sensor and protect it from excessive heat coming up from the cat/block/manifold --see if that helps/changes things
i thought that the heat is maybe messing with one of the sensors? till it dissipates then not do it. it did it whether or not i had locked the car or not. meaning even unarmed the alarm would sound.

I removed #19 fuse under seat which my research yielded was the defroster and alarm fuse,... it still sounded off wtf

 

So I drove 45 min
to town
Got there off hwy, died

Got it into parking lot

No cel, but Got on obb2 reader
P0100, and p0110.

Air flow and air temp sensor.

Maybe guess I need them replaced....
No cel. But that's what reader is giving
p0100 and p0110

 

Time for a new MAF sensor I suppose. I'd recommend only using Bosch.

 

CPS usually does not throw a code. Usually fails when hot and will restart when it cools off. They are pretty cheap and easy to replace.

 

fails when hot and works again when cooled.... that is kinda like what i am experiencing now

so i wonder though... if it works when cooled down, and fails when hot---is that an indication that is it bad cps??? or would even a perfectly fine cps have same trouble

bc and i only ask ...bc since the new cats are in, it really feels as though the engine compartment (upon lifting hood) is soooo much hotter than before... just kinda feels real hot and smells hot.
but i am not getting overheating signs in car, but sticking head over the engine and over the cats thru that space there- is really warm. i have infrared thermometers and i can measure the temps of surfaces in/around the area/s of cps or maf.

I got a fuel line pressure tester - and will hook that up when i get home tonight.

but to get folks caught up to speed, i have a NEW Bosch MAF sensor on its way

maybe i also do the cps. but my question kinda still stands though- would a perfectly running cps fail or not work great if it got too hot.---or bc it is bad that this fail due to temp occurs?

I have even thought of taking some rockwool, and aluminum foil and insulating the MAF sensor --or try to anyways from the heat and see if that makes any difference

 

Usually means the CPS is failing.

 

tested fuel pressure ---im gonna jump out there and say that im where i should be
i dont have the data base of what psi i should have but on YT i am seeing/hearing that my psi should be between 45-55 ish psi

well i had 45psi at first click of key and once started i was at 50-55 ish

 

the crankshaft position sensor only costs about $40 USD and is about a 30 minute replacement. these occasionally
go out and can be very frustrating since the symptoms are sporadic but generally come to life (die, actually) when
engine is hot. once it cools, it acts normally...over and over. it may be a simple thing to try (like 1999E320 suggested)

scroll down and check under CRANKSHAFT POSITION SENSOR and see what you think

 

ok yeah i agree - i will get a new one

but the videos i saw i guess there are a couple different types. so i will look see which one it is i have and get the right one

but i agree ...from yt vids and stuff i think it could also be cps failure when hot
- and one of the videos i watched the guy said his failed right around 89k miles, mine has 92, so it sounds fitting to replace that and

the maf sensor will be here tomorrow and i think local shop has teh cps they can have here in just a day or so.

thx!

 

is there a better brand of cps to get vs 3rd party?

the local store tells me that they offe a importdirect brand and said it was/is a very good brand?...? what say you guys?

 

Use only a Bosch CPS.

 

MAF sensor showed up today
threw that in,
not getting all the misfire codes as before,
but still getting MAF circuit --but i haven't cleared them yet either.
but it says pending--what's that mean, its just not confirmed yet or somthing...tbh idr if it was there last time or not, but maybe explains why there is no CEL on
ALSO it reads MAF circuit---is that trying to tell me maybe its the harness/connector or smth? that is issue vx maf filter sensor? or idk maybe they just using the term loosely and the circuit that normally fails is the sensor end of it, the business end of things?

 

so went out and cleared codes

didn't read again jonnie on the spot, fired it up and drove 1m down street
and came back as it started to stall on me at light
came right back

So the bosch CPS is next
ftr the MAF Sensor was bosch

 

is it possible that it could be fuel pump? even though it is demonstrating proper pressure on a 5 min test
can the fuel line tester like just stay on for 20 min and see if pump maybe fails over a duration of time?

 

what i find so perplexing tho tbh
is that i need to change the cps, but throws a pending code of MAF circuit
so like is it always kinda like this or just this case with the cps and not throwing codes for the cps? Not even a pending one

imma go out and read again now that i am back & it's cooled and stuff

 

Don't waste any more time until you get the CPS replaced.

 

right on right on
i got it out ---took 30 min for the one damn screw, but yt very helpful

part in thursday


so excited, i bought the car in janurary and been dying to drive it and not worry about breaking down
but i bet before the cats clogged up on me, that the cooler weather is what maybe made the cps a non-issue
until hotter weather when i got it back
dropped it off in early march and got it back like week or so ago- 88f out and that prolly the cps issue then reared its head with hotter temps