Can not figure out miss/ stall while idling.. please help

SgtDan94

New Member
May 1, 2021
2
0
1
27
North Carolina
I have 95’ 5.0 That is missing and near stalling during idle. About every ~ 5 seconds, RPMs drop and engine saves itself from dying.

So far I have replaced the O2 sensors, MAF, TPS, IAC, alternator, motorcraft spark plugs (gapped correctly), distributor, engine grounds, checked for vacuum leaks, and tested the battery, but still, no change.

i know there must be a bad ground somewhere, because my temp and oil gauges are a little whacked out. Also, it takes about 5-7 cranks to start up when engine is cold (average 70 degrees outside).

Stang has 130,000 miles on it and is in good shape, mostly stock besides a cold air intake. I’ve run through the rough idle check list and still cannot figure out what is going on.

I know there are many posts about this. I spent a lot of time researching before deciding to post a new thread.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,889
6,690
193
polk county florida
Let me be the first to jump in.
Did you check for codes?
You did the 'surging idle checklist' step by step paying attention to the color print that references the difference in the 94-5 procedure?
 

SgtDan94

New Member
May 1, 2021
2
0
1
27
North Carolina
Let me be the first to jump in.
Did you check for codes?
You did the 'surging idle checklist' step by step paying attention to the color print that references the difference in the 94-5 procedure?
I followed is step by step the best I could with what I have available to me.. some things I didn’t do was check the TPS voltage, or really go in depth with the vacuum lines.. I intend on replacing all of them soon..

I did have a theory.. the previous owner installed a BBK cold air intake and left the stock ford MAF on... would the increased airflow from the BBK intake cause idle issues??
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,889
6,690
193
polk county florida
I followed is step by step the best I could with what I have available to me.. some things I didn’t do was check the TPS voltage, or really go in depth with the vacuum lines.. I intend on replacing all of them soon..

I did have a theory.. the previous owner installed a BBK cold air intake and left the stock ford MAF on... would the increased airflow from the BBK intake cause idle issues??
The stock maf likely is not the issue, you can't theorize car repairs on computer controlled stuff unless you have nothing better to do with your time/money.
You need to gather the tools together to complete the checklist step by step.