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1989 Mustang 5.0, Sputters and Smokes at High RPM

  • Thread starter Thread starter roadrunner_taz
  • Start date Start date Apr 29, 2008
R

roadrunner_taz

New Member
Apr 29, 2008
3
0
0
Apr 29, 2008
#1
  • Apr 29, 2008
  • #1
I have a 89 5.0. Mods are: aluminum heads, rockers, headers, 75MM TB, Fuel pressure regulator, 190 lphr fuel pump, hypertech chip, 373 gears.

My question is my care runs great under normal conditions but when I really get on it and put it to the floor it feels like a sputtering or no power at about 4000 RPM. I notice this a little in 3rd gear but it is really bad in 4th gear. If I let up on the throttle say 3/4 throttle I actually will have more power then if it is all the way to the floor. Also when it bogs down like this I notice white/blue smoke coming out the exhaust and can smell that it is burning oil.

I initially thought it was a lack of fuel problem so I added the bigger fuel pump and changed the filter. This did not help. Engine is not pinging but I decided to try to set my timing from 14 and to about 10 and that did not help. I had put in new plugs and wires when I put my heads on so they are pretty new.

This is a new problem that just started so it is not from the new head install. I also checked my head gasket and that is not the problem. Please Help!!!
 

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Apr 29, 2008
#2
  • Apr 29, 2008
  • #2
well you might have a cracked ring, I smoked my engine and it did the same thing, no power smoking etc..... check compression, leak down and so forth, pressurize the coolant system and see if you get any leaks as well..
 
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