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Discussion Starter · #1 ·
I just drove my car home yesterday. When the car first starts up after it quits idle surging and you start driving it drives fine.. then after it heats up it drives like total S***. It has hardly any power, sucks down gas, and every time you give it the beans, it starts popping and hesitating till you get above about 2500rpms then it moves a little. Then when i stop at a light it will idle at 2k. The timing is set up on it right now, idles at 1k cause anything less and it wont even stay running or whenever you hit it it will just start popping really loud. Well i was driving to the gym and i push it, nothing, downshift, nothing. so I noticed oil pressure going down again so I just stopped and let it sit there for a few minutes and drove it home.
Does this sound like anything anyone has encountered before? Help me before i lose it here.. :(
does this sound like maybe the cam I have is just ever so slightly larger than it should be?
It is a speed density car.

list of things replaced.
Cam + lifters (supposed to be stock cam) mine was grinded down.
lifter retainer (that spider thing)
distributor, rotor cap, distributor cap
idle air control valve
fuel filter
GT40 heads with 1.7 crane rr (lash caps to make the rr noise stop)
GT40 intake
 

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my car did this before but later i found out that my mass airflow sensor was fried up so my car was running very wierd. make sure you have the right amount of anitfreeze in the car too, i also had another problem with my car, the thermostat was bad, it said i had good temperature but later it would jump and id be running hot, my car also acted up like yours, a engine will act a hell of alot diferent when it gets hot. same goes with the tranny.
 

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Discussion Starter · #4 ·
my car did this before but later i found out that my mass airflow sensor was fried up so my car was running very wierd. make sure you have the right amount of anitfreeze in the car too, i also had another problem with my car, the thermostat was bad, it said i had good temperature but later it would jump and id be running hot, my car also acted up like yours, a engine will act a hell of alot diferent when it gets hot. same goes with the tranny.
yeah my car doesn't even have a maf..
I do have a maf conversion though.. just waiting to go down.. hmm
 

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hmmm interesting, and my stang is a 90, im going backwards and going old school with a 302 engine swap from my 66 stang and im gunna have mine carberator. i hate computers. but sounds like there is something wrong with the computer in your car, a engine will not just act that way on its own from outa nowhere. something is def wrong.
 

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I don’t know if this is your problem or not but have you checked your fuel pressure? If your fuel pump is getting weak it will give you those problems. It just sounds like a fuel issue to me.
 

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Discussion Starter · #7 ·
I don’t know if this is your problem or not but have you checked your fuel pressure? If your fuel pump is getting weak it will give you those problems. It just sounds like a fuel issue to me.

last time the fuel pressure was checked it was normal..
here is a video i made yesterday.. idk if this will help any.. this is just an idle.. i didnt touch the pedal any

YouTube - 88MustangGT
 

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By any chance have you checked your MAP sensor? Now I'm not sure but I think the ECM has a set parameter it runs off of if the sensor is unplugged. If you unplug it and it runs better I would say that your MAP sensor is bad or you have a bad vacuum line running to it.
 

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Discussion Starter · #9 ·
By any chance have you checked your MAP sensor? Now I'm not sure but I think the ECM has a set parameter it runs off of if the sensor is unplugged. If you unplug it and it runs better I would say that your MAP sensor is bad or you have a bad vacuum line running to it.
Yep checked that. It's good..
Perhaps I just need to do that MAF conversion.. I already have all the stuff.. guess it just needs to go down :?:
 

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I would check all your vacuum lines. I wouldnt rush into the mass air swap just because you have this problem, it might not go away when you change over. Sounds like a vacuum line is leaking somewhere. There could also be something up with your thermostat. id check all the connections around your egr. as far as the wierd idling, its a mustang, its almost inevitable. check out your throttle postion sensor voltages
 

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Discussion Starter · #11 ·
Just letting everyone know..
I did get the car running right, after the MAF conversion the computer needed a little time to relearn. Miraculously the car runs like a charm :bigthumbsup
 
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