B492bulldog Posted July 17, 2010 Share Posted July 17, 2010 When I'm pulling up through the gears all of a sudden it is like you shut off the key just for a second and then back on.Does it so fast you cant even get your foot off the fuel so it jerks like crazy when it does it.Put new air and fuel filters on and still does it.No codes and no faults.What do I need to check next???? Quote Link to comment Share on other sites More sharing options...
Gambi80 Posted July 17, 2010 Share Posted July 17, 2010 Gas pedal. Quote Ever wonder how a blind person knows when to stop wiping? Link to comment Share on other sites More sharing options...
rhasler Posted July 17, 2010 Share Posted July 17, 2010 When I'm pulling up through the gears all of a sudden it is like you shut off the key just for a second and then back on.Does it so fast you cant even get your foot off the fuel so it jerks like crazy when it does it.Put new air and fuel filters on and still does it.No codes and no faults.What do I need to check next????Check the ground connections on the batteries, at the starter, engine block ground, frame rail ground, alternator ground, cab ground breaker, and the left side cab ground for loose or bad connections. If everything is ok in those areas you may have a power relay (to the left of the cab fuse panel there is a row of 4 relays) that is going bad. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
B492bulldog Posted July 17, 2010 Author Share Posted July 17, 2010 Check the ground connections on the batteries, at the starter, engine block ground, frame rail ground, alternator ground, cab ground breaker, and the left side cab ground for loose or bad connections. If everything is ok in those areas you may have a power relay (to the left of the cab fuse panel there is a row of 4 relays) that is going bad. Quote Link to comment Share on other sites More sharing options...
B492bulldog Posted July 17, 2010 Author Share Posted July 17, 2010 OK Thanks.I will check out that stuff and see if that cures it. Quote Link to comment Share on other sites More sharing options...
Noid93 Posted July 17, 2010 Share Posted July 17, 2010 My 97 does the same thing. All i do is make sure the wires going to the gas pedal have plenty of slack through out the entire movement of the accelorator pedal. Somehow the wires works themselves backwards through the wire saddle until its tight. Check the conector for corrosion and grease with dielectric grease and it should be good for a year or so.... Quote There Is No Replacement, For Displacement!!!!! Link to comment Share on other sites More sharing options...
sixtynineford Posted August 24, 2010 Share Posted August 24, 2010 I drive a 99 460 truck that does the same thing but only at 1450-1550 rpm, have changed cam and crank sensor, cleaned triangle connector on firewall and changed gas pedal to no avail.... Quote Link to comment Share on other sites More sharing options...
rhasler Posted August 24, 2010 Share Posted August 24, 2010 I drive a 99 460 truck that does the same thing but only at 1450-1550 rpm, have changed cam and crank sensor, cleaned triangle connector on firewall and changed gas pedal to no avail....Check the belt tensioner (as goofy as that sounds). If the tracking mark is wider than the belt it indicates that the tensioner is worn out. If the tensioner is worn it can set up a vibration through the front cover on the engine which is then transferred to the camshaft sensor. There is a revised front cover with a gusset to reinforce the camshaft sensor. Being a 1999 truck it's also possible that there is wear to the camshaft thrust washer allowing the distance between the cam and sensor to change during operation. Additionally there might be a service datafile to help with this problem. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
redman Posted August 24, 2010 Share Posted August 24, 2010 i had the same thing with my 97 427.after going through everything fuel and electrical at the dealer,it turned out to be the sensor that times the engine off the back of the flywheel.i forget what its called but it took along time to figure it out. Quote Link to comment Share on other sites More sharing options...
BakerSmith Posted September 3, 2010 Share Posted September 3, 2010 The most familiar gear problem in manual transmission cars is actually not in the gears but in the clutch. For many the clutch is the core system that makes a manual car different from an automatic. Clutches normally last up to 80,000 miles, but they will break down quickly with improper use and this is part of the design. The clutch is supposed to fail first before the damage of shifting and changing gears translates to the gears themselves. so my suggestion is to check cluth setting from engineer. Quote Link to comment Share on other sites More sharing options...
hatcity Posted September 3, 2010 Share Posted September 3, 2010 The most familiar gear problem in manual transmission cars is actually not in the gears but in the clutch. For many the clutch is the core system that makes a manual car different from an automatic. Clutches normally last up to 80,000 miles, but they will break down quickly with improper use and this is part of the design. The clutch is supposed to fail first before the damage of shifting and changing gears translates to the gears themselves. so my suggestion is to check cluth setting from engineer.Ah, the voice of reason and sensibility returns. Quote Success is only a stones throw away.................................................................for a Palestinian Link to comment Share on other sites More sharing options...
vision386 Posted September 3, 2010 Share Posted September 3, 2010 Ah, the voice of reason and sensibility returns.No doubt! he's hard at work in his "lab" coming up with pertinant answers to all the technical questions we might have on here!.........Mark Quote Mack Truck literate. Computer illiterate. Link to comment Share on other sites More sharing options...
RFC Posted September 3, 2010 Share Posted September 3, 2010 You have a short. We have the same problem with our 460. Good luck finding it:) Quote Link to comment Share on other sites More sharing options...
B492bulldog Posted September 12, 2010 Author Share Posted September 12, 2010 The truck has been at the Mack garage now almost 2 weeks.Last I heard they were going to install a new wireing harnrss and if that doesn't fix it They are going to get somebody from Allentown up to Erie to look at it. Quote Link to comment Share on other sites More sharing options...
CompToyZ Posted September 28, 2010 Share Posted September 28, 2010 (edited) Mine does the same, I have a leaky sight glass and seemed to be happening when my coolant was low, well yesterday with all myfluids topped up and using cruise it happenned again Edited October 25, 2010 by CompToyZ Quote Link to comment Share on other sites More sharing options...
B492bulldog Posted October 30, 2010 Author Share Posted October 30, 2010 Well good luck with it.I got mine back from the Mack garage awhile ago and it still does it occasionally.I cant figure out a common denominator It is just a random thing that is driveing me crazy. Quote Link to comment Share on other sites More sharing options...
nyou22 Posted December 26, 2010 Share Posted December 26, 2010 Mine did the exact same thing took dealer all day on the dyno trying to replicate. Turned out to be contact discs in the starter solenoid touching mounting bolts.Hope this helps. Quote Link to comment Share on other sites More sharing options...
bobo Posted December 26, 2010 Share Posted December 26, 2010 Check cam/crank censor clean it off. If it's got 1 gasket add another, so there is 2. If has 2, take 1 away. Bobo Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.