Tachometer problems
Thread Starter
|
New User
Joined: Jul 2005
Posts: 6
Likes: 0
Tachometer problems
Hi, I have a 87 f250 with a 6.9, the tach sits on 0 when the truck is not running when started it goes backwards to 4200 redline I already replaced the sensor at the injection pump. (help) Thanks in advance.
New User
Joined: Aug 2005
Posts: 8
Likes: 0
I have a '91 with a similiar problem, except perhaps even more erratic (sometimes goes backwards like you describe, sometimes just goes really fast forward, way faster then the engine is actually revving). I also replaced the sensor, since that is apparently what usually goes out, and I tried to trace for shorts, but to no avail. Current thinking by my mechanic is that its the actual tach in the dash, but since that is ~>$300 and I usually shift by ear anyways, I haven't replaced it.
Posting Guru
Joined: May 2004
Posts: 2,161
Likes: 1
From: Prince George, B.C.
It is possible that the Tach in the dash is doing this but I should also ask, how are the other guages functioning? A tach from the wreckers should be cheap.
Trending Topics
New User
Joined: Aug 2005
Posts: 8
Likes: 0
I don't know about Lil Abner's but all the rest of my guages work just fine. I haven't pursued used tachs, but probably will. I think its a pretty rare failure, so a used one should be a good risk.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Thread Starter
|
New User
Joined: Jul 2005
Posts: 6
Likes: 0
Iam also in the same boat with bbbranch just joined this forum no email privleges.My main concern for the tach is it sounds like my engine is revving to much before shifts ,(c6 auto) shifts at 27mph and 48mph 3:54 axle is this normal thanks
New User
Joined: Aug 2005
Posts: 8
Likes: 0
(glad mine's a stick) 
If its affecting the shift points, then I would *think* that its more then the tach in the dash. Unless the trans is getting its info from the tach, but I would think it would be taking it from the sensor directly, which you've already replaced... hmmm...
Hopefully some smarter person can help you out
If its affecting the shift points, then I would *think* that its more then the tach in the dash. Unless the trans is getting its info from the tach, but I would think it would be taking it from the sensor directly, which you've already replaced... hmmm...
Hopefully some smarter person can help you out
Post Fiend
Joined: Nov 2004
Posts: 5,638
Likes: 1
From: Manitoba
Lil Abner do a signature re the info about your truck..... go to Quick links at the top and put all the info you can........ we all refer to that info for correct answers to your problems as there are several different systems for different years......thanks.