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Fuel Pressure Gauge install

3K views 16 replies 6 participants last post by  Cowboy303 
#1 ·
Since installing a fuel pressure gauge my truck shudders under load. When I installed the banjo bolt fuel spilled out of the fitting and it took some cranking to get it started again after the install. Seems to run fine otherwise. Could I have air in the IP or could my problem be transmission related and nothing to do with the gauge install. The problem started this weekend coming home from CT, but wasn't apparent the week before on a trip to Rochester NY before the gauge install. Bot times pulling a 5K camper.
1996 Automatic with no mods, 181K miles
 
#2 ·
Using a little common sense, where do you think the air would be? Once the engine has started whatever air is in the system purges quickly if the rest of the system is good.
 
#5 ·
Just thought I'd ask since it didn't happen before I installed the gauge.
You answered your own question. Gary basically pointed out where the air leak is.

Go over your gauge install and find where air is getting in.
 
#4 ·
Sometimes it feels like I'm driving on a washboard road, other times, for a few seconds, it's very violent. Makes everything in the truck shake. Talked to the shop that rebuilt the tranny and he said if it shook that much and it was the tranny I'd still be in CT.
 
#7 ·
Yes. I don't think you have any air in the system. But if you think the fuel pressure gauge installation could be at fault, remove it and cap the hole in the banjo bolt. I can tell you from multiple R&Rs of the flex hose that I never had any shudder under load. I think you have a trans problem.
 
#8 · (Edited)
I will chime in and say : are you getting any kind of smoke out the tail pipe and what kind of fuel pressures are you reading?

I tow a rather heavy horse trailer so I know the feeling of AH! Oh No! is my trany dying on me! And the feeling of being really aware of every detail of how it usually feels---so when something changes it's like "princess and the pea" you just know something is different than usual

I'm not a gear head but I can say some easy checks can be helpful if you have not already-like

1.) does OD off button work, if yes, if you turn OD off so you stay in 3rd do you still shudder
2.) cruising steady like 45-50 so it's in 4th/ OD keeping foot steady on gas, if you tap your brake pedal with your left foot does it down shift to 3rd like it should
3. ) parked in driveway check fuel pressure at idle and reved up 2500 rpms make sure they are within spec OEM OFV's and the popular Tork Tec OFV's have slightly different specs for pressures---sorry don't have the info in front of me but you'll find plenty in these forums
4.) if your fuel pressures are looking "weird"---do return line pinch test etc.
5.)reving up and down just in driveway do you get any smoke, stutter/pulse anything different

I will also mention-- I don't know that the symptom you are describing really "matches" but, I was towing one day perfectly fine, fortunately dropped horses off, and returning home with trailer all of the sudden it was hunting up-down-up-down-up-down like crazy between 3 and OD. I thought OH NO! My OD lock out worked fine and I could lock out and stay in 3rd and not keep shifting up and down like crazy (cruise speed 45-50+) I was scared and took it to a shop expecting worst----was TPS switch. I opted to have a new one put on I think 4 years ago $120 and problem was solved everything fine.

Also I'm going to mention----because I just had a problem with it myself--and it doesn't necessarily match your symptoms but a "what the heck" easy enough to check--- driver side positive battery post has big clamp with a bunch of other things bolted to it. There are a number of important things connected there. I found mine were very loose and may having been causing weirdness with my FSS

Speaking of FSS-----when you put in your fuel pressure gauge you worked around that bunch of electrical connectors and "stuff" above the fuel filter that is totally in the way of your hand/arm wrenches---make sure they are all snuggly/correctly attacked now. One of them is connected to the fuel shut off solenoid

also-- just in case-- check your throttel cable for fraying and correct movement

air filter----I recently had a family of mice in mine ;0( I had to evict them TWICE! I was busy had truck parked for week or 2 both times....after finding baby mice inside the door ;0( when I got in (load pitiful squeaking...) I figured I should check any other places that could make a cozy mouse aboad and found a nest in air filter --having them sucked thru the turbo fan would have upset me and the turbo I think.

another simple one-- be sure tires and front end are OK. I once had a new wheel bearing (installed by a garage...) self destruct and start binding---it made my front end feel like it was hopping up and down with wild animals raging under the hood. Also I once had a bunch of stuff done, tie rods, track bar etc. whatever it was it threw off the alignment and the guy that did it "spaced out" and didn't check to get the alignment even close---just threw the stuff on----well, I drove away and thought I was going to die---the front end was all over and vibrating like the truck was going to blow up----took it too a quick alignment and miraculously 100%cured---so I can tell you that stuff does /can make a huge difference.

these are just simple things easy to check at home ---may help may not---if you are doin it at least it's FREE ;0)
 
#9 · (Edited)
I just remembered something else--- you can get some additional ideas about a transmission source by finding a safe quiet stretch of road and get it shuddering-- --take foot off pedal does it change/go away --- shift it into neutral does it change go away ( joints on the drive shaft will rumble/ vibrate when bad and it can be worst when you are under load with force driving them and better when coasting, center bearing is one to check because it seems to catch a lot of people by suprise...occasionally when it drops to the pavement whilst driving!

and definitely do the fuel system trouble shooting tests-- like pinch return line because I just have frigged around chasing fuel/power issues----and lots of things when you read descriptions over lap symptoms--- the pinch return line should tell you easy peasy if the OFV and Lift transfer pump are ok---- your symptoms do kind of fit description and experience some people have had with either being iffy---very easy to test with your pressure gauge.
 
#11 ·
I think Games is right. I found a stretch of smooth new pavement on a slight incline. Ran the truck for about an hour and then drove on the new pavement. No load but in OD on the incline I could feel a slight bucking. Kinda like driving on a wash board road. Slip into neutral and it stopped. Back into OD and its back. This morning I started the truck and went straight to the test road. Only about a mile away. No bucking. Looks like only when the tranny is hot. I'm going to put the original banjo bolt back in just to be consistent but I think I'm looking at tranny problems.
 
#12 · (Edited)
Pulled the Fuel Pressure gauge and re-installed the original Banjo Bolt. Didn't change. Had rear grease seals replaced and the drive shaft and center bearing checked. All new an no problems found. Also replaced the TPS. I think the lockup clutch is slipping. Might look into increasing line pressure or raising shift points with the TV cable. Any thoughts?:banghead:
Anyone know a good Transmission shop near Albany, NY?
 
#13 ·
#15 ·
Talked to the shop that built the transmission today. He said that the pressure adjustment is backed out all the way because of the after market valve body he put in. Also said I should put in 2 bottles of "lubegard" in the red bottle in. Anyone ever heard of "Lubegard"?
 
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