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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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351w Roller Issues

  • Thread starter Thread starter Stang_1973
  • Start date Start date Sep 22, 2017

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Sep 22, 2017
#1
  • Sep 22, 2017
  • #1
So guys i have a couple issues that my car has developed over the years that seem to be getting worse.

Im posting in here because my '73 setup is based off a 1990 mustang setup. A9L computer and harness, running a 351W roller cam engine sitting in front of an nonlock up AOD with lentech valvebody.

so here are my two issues.

the first is that this engine has about 15k miles on it since it was isntalled years ago. the car doesnt get driven all that much really. but ever since ive had it, i noticed it seems to burn oil or lose oil anyway. there is no blue smoke, and no little puddles where ever i park it. it can sit for over a week without being moved. that said, at times when i do drive it more heavily it seems im always having to add oil. maybe 1 quart after a month of say 300-500 miles. again no blue smoke, no puddles. also the coolant looks clean.

next issue is after turns there is definate hesitation and sometimes backfiring. usually happens when i turn left. have no idea what can be causing this..

any ideas?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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polk county florida
Sep 22, 2017
#2
  • Sep 22, 2017
  • #2
What do the plugs look like?
And if you make enought right turns you don't need to turn left.
Can you mount a fuel gauge some place safe that you can watch?
Have you checked for codes?
 
Reactions: imp

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Sep 23, 2017
#3
  • Sep 23, 2017
  • #3
karthief said:
What do the plugs look like?
And if you make enought right turns you don't need to turn left.
Can you mount a fuel gauge some place safe that you can watch?
Have you checked for codes?
Click to expand...


have not checked the plugs. will try and pull a few to check them out? anything in particular i should be looking for?

fuel gauge on the car is connected and works. however not sure how reliable it is. sometime i pump gas till the pump clicks but my guage will show only 3/4 tank full. sometimes shows full. sometimes when it gets to the 1/4 tank i can hear the fuel pump buzzing which ive heard means its starving for gas, other times the gauge gets right to the E with no issues.

Now if you meant a fuel pressure gauge. the only one is mounted in the engine bay. reads @ 40 or 43 PSI and if you accelerate it climbs up. this is in park however, and ie done it bith with the vacumm line connected and disconnected. similair results. however i havent been able to check fuel pressure while driving.

When we put this project together, the guy who did my install tuned the A9L computer which is installed under the glove compartment. not sure how i could check for codes, or if by clearing stuff i risk clearing out the tuning as well.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,955
10,598
203
polk county florida
Sep 23, 2017
#4
  • Sep 23, 2017
  • #4


Here is a pic of the connection for the code reader in a fox. See if you can find it and the single brown connector. There is a thread in the tech/how to threads on pulling codes without a code reader using a test light, I figuare you will not have a check engine light.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 24, 2017
#5
  • Sep 24, 2017
  • #5
pulling/clearing codes won't negatively impact your tune. Finding that diagnostic connector could be an adventure, assuming it was installed. I would start in the area of the computer... at least that is where I would put it...
 
Reactions: General karthief

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Sep 25, 2017
#6
  • Sep 25, 2017
  • #6
Ok i got up under the car to do an oil change today and found a mess. im guessing this is where my oil has been going. prolly not enough to make a puddle or its burning off. considering that whenever i drive the car, after its hot and you get out i often smell something burnt, kinda like burn popcorn. im guessing this is what it is. judging by the location, right between the tranny and engine, im guessing its the rear main seal. everywhere else is clean, except for the around the filler neck on the head cover. for some reason i always have to clean up oil around filler neck. see pic for underbody oily mess.
 

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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,955
10,598
203
polk county florida
Sep 25, 2017
#7
  • Sep 25, 2017
  • #7
Could be a rear main seal, thats a drag.
 

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Sep 25, 2017
#8
  • Sep 25, 2017
  • #8
dropped the car off at my shop today. getting the rear main seal looked at.

After i get it back, ill keep looking into the hesitation after turns.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 28, 2017
#9
  • Sep 28, 2017
  • #9
Might want to have them check compression/leak down?
Or do it yourself, especially since you are getting oil from 2 different places
 
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