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new engine issues

  • Thread starter Thread starter 1bad86GT
  • Start date Start date Apr 1, 2005

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 1, 2005
#1
  • Apr 1, 2005
  • #1
Well, I finally got my new engine installed and running, but now I have a few bugs that need to be worked out. First of all my combo is this: 1986 mustang GT, 5 speed, 308 crate engine with TFS TW heads, TFS stage 1 cam, 75mm Pro-M mass air, 70mm throttle body, TFS street heat intake, BBK longtube headers, new 190lph fuel pump, new FMS 24# injectors, mass air conversion. The engine runs fine, except will start cutting out at 4500-5000rpm in any gear (even neutral). I have an adjustable fuel pressure regulator that is set at about 40lbs, but we have tried different settings and it makes no difference. It seems to be running pretty lean, the plugs are kind of white. Anybody have some ideas?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Apr 1, 2005
#2
  • Apr 1, 2005
  • #2
Check voltage at TPS, check rotor and cap for wear/damage.
 

dstanggt50

Founding Member
Sep 13, 2000
1,316
0
0
Woodinville, WA
Apr 1, 2005
#3
  • Apr 1, 2005
  • #3
I had a similar problem when my maf went bad, maybe check voltage of the maf if you can ( I used a snap on scanner at my old work), any codes?? Maybe check the little things, vacuum leaks, timing , f/p.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Apr 1, 2005
#4
  • Apr 1, 2005
  • #4
Also another thought..check the TFI module...could swear I remember reading about simular issue/cause.
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 1, 2005
#5
  • Apr 1, 2005
  • #5
forgot to mention, I put on a brand new MSD cap and rotor set, a new MSD blaster coil, and a new Accel TFI module. The mass air meter is also brand new. Also when I started the engine for the first time, I had two spark plug wires crossed, so it was popping and backfiring through the intake and TB. Could this have damaged anything?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Apr 1, 2005
#6
  • Apr 1, 2005
  • #6
doubt it..would look at ignition issue..like the coil then
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 1, 2005
#7
  • Apr 1, 2005
  • #7
so you think the new coil might be bad? would the TFI module do this? it runs fine below 4500.
 

dstanggt50

Founding Member
Sep 13, 2000
1,316
0
0
Woodinville, WA
Apr 1, 2005
#8
  • Apr 1, 2005
  • #8
if it is an actual "lean" problem, I think there can only be a few things related. Either maf, o2's, fuel pressure, vacuum leaks ( not sure about that one), and maybe a couple of other sensors (IAT, Coolant temp???) Are there any codes?? If there are no codes, (thats what happened to mine, had to get it replaced twice,from pro-m, only way i knew was that I measured voltage of the maf), maybe a vacuum leak, maybe you check vacuum, make sure there are no leaks. I don't think a TFI would cause an issue like that, but you could always replace it w/the stock one if you have it. If you had the stock coil, maybe put that back on to see if that helps, along w/the stock maf, just to see if the sputtering goes away at high rpms. Sometimes new parts can have something wrong with it, it doesn't hurt to try to stock stuff just to see if it helps, it'll only be temporary. I would also make sure your valvetrain is set correctly.
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 3, 2005
#9
  • Apr 3, 2005
  • #9
well, I'm going to start checking stuff tomorrow. also, I was wondering how it should be driven since its new, like breaking it in. I've been running the dog**** out of it trying to figure it out this problem, at high rpm, and it only has like 50-100 miles on it. does this hurt anything?
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 4, 2005
#10
  • Apr 4, 2005
  • #10
should there be some kind of break-in period?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Apr 4, 2005
#11
  • Apr 4, 2005
  • #11
Depends on who you ask..I baby mine with 100miles on it, probably for another 2 or 3 hundred, but it's a topic of great debate on what to do. I suggest you make a point of changing the oil a couple times in the first 1000miles and just drive it like you would normally. I only baby mine because I'm a little old school and doing so makes me feel warm and fuzzy inside. Good luck.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Apr 4, 2005
#12
  • Apr 4, 2005
  • #12
shoulda went with an MSD distributor also instead of a vamped up stocker....just my .02
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 4, 2005
#13
  • Apr 4, 2005
  • #13
could the distributor cause the missing issue at high rpm? it seemed fine when we put it in but it does have a lot of miles on it. there's so many things to check, I don't even know where to start. so far we've adjusted the fuel pressure, tried a different computer, changed the timing.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Apr 4, 2005
#14
  • Apr 4, 2005
  • #14
Did you grease the TFI before installing it?? heat can affect it if you did not. The grease is usually supplied with the TFI unit in the box.
 

1bad86GT

Founding Member
Jul 18, 2002
137
0
16
S.A. Texas
Apr 4, 2005
#15
  • Apr 4, 2005
  • #15
yeah, we greased the TFI module. anything else inside the distributor?
 

feifong

New Member
Apr 4, 2005
319
0
0
mesa
Apr 4, 2005
#16
  • Apr 4, 2005
  • #16
cc

there is a break in period put at least 2000 miles before you go faster than 65 lol
i had an unk who built a motor and took it for a trip without break in and popped on him
 
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