Stalling and poor throttle response
#16
12-12-2017, 05:13 PM
Join Date: Dec 2012
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
Really check that you are getting fuel pressure to the IP under load, and there is no air in it.
A little bit of air will cause this sort of thing - "starving" for fuel. Unlike a gasser, it won't choke or anything, just... not have as much power.
Cold advance and high idle only affect it when it's cold; up to operating temp and you only have the shut-off solenoid in play.
Check if it happens longer with the blower fan on max and less/disappears with it's off.
While it /shouldn't/ happen, depending on how things are wired, the blower fan will become a generator as it spins down and keeps enough power to the solenoid to keep it energized for a few seconds... IF it's not isolated by a switch which I THINK normally happens.
A little bit of air will cause this sort of thing - "starving" for fuel. Unlike a gasser, it won't choke or anything, just... not have as much power.
Cold advance and high idle only affect it when it's cold; up to operating temp and you only have the shut-off solenoid in play.
Check if it happens longer with the blower fan on max and less/disappears with it's off.
While it /shouldn't/ happen, depending on how things are wired, the blower fan will become a generator as it spins down and keeps enough power to the solenoid to keep it energized for a few seconds... IF it's not isolated by a switch which I THINK normally happens.
Thanks for the info
#18
12-12-2017, 06:26 PM
Still sounds like an IDI. I've lost speed pulling downhill before...
#19
12-12-2017, 08:32 PM
Join Date: Dec 2012
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
So.... I put a test light on the fuel valve , seemed to be pretty consistent with the key switch electrically , so I am left to believe it is the valve itself leaking by or dirty possibly.
Just for the heck of it I energized the cold advance after she came off the switch and it didn't really seem change in clatter to me, but the rpms came up a hair...
Next was fuel pressure/volume test... the adapter for my gauge wasn't cooperating so I didn't get a pressure reading, but in apx 15-19 seconds I filled 8 oz roughly.(half a water bottle/pint-ish)
so I read somewhere that 30 seconds should net you a pint, so hopefully I counted to fast...
Just for the heck of it I energized the cold advance after she came off the switch and it didn't really seem change in clatter to me, but the rpms came up a hair...
Next was fuel pressure/volume test... the adapter for my gauge wasn't cooperating so I didn't get a pressure reading, but in apx 15-19 seconds I filled 8 oz roughly.(half a water bottle/pint-ish)
so I read somewhere that 30 seconds should net you a pint, so hopefully I counted to fast...
#20
12-18-2017, 09:24 PM
Join Date: Dec 2012
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
So.... I put a test light on the fuel valve , seemed to be pretty consistent with the key switch electrically , so I am left to believe it is the valve itself leaking by or dirty possibly.
Just for the heck of it I energized the cold advance after she came off the switch and it didn't really seem change in clatter to me, but the rpms came up a hair...
Next was fuel pressure/volume test... the adapter for my gauge wasn't cooperating so I didn't get a pressure reading, but in apx 15-19 seconds I filled 8 oz roughly.(half a water bottle/pint-ish)
so I read somewhere that 30 seconds should net you a pint, so hopefully I counted to fast...
Just for the heck of it I energized the cold advance after she came off the switch and it didn't really seem change in clatter to me, but the rpms came up a hair...
Next was fuel pressure/volume test... the adapter for my gauge wasn't cooperating so I didn't get a pressure reading, but in apx 15-19 seconds I filled 8 oz roughly.(half a water bottle/pint-ish)
so I read somewhere that 30 seconds should net you a pint, so hopefully I counted to fast...
#21
01-02-2018, 05:13 PM
Join Date: Dec 2012
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
Well, going to attempt an atf in the filter trick .. I’ve pulled feed and return lines off of pump, all looks squeaky clean... throttle moving ,plunger doesn’t look stuck..
Try to take a pressure test one last time just for confirmation, after that I guess it’s just time to throw an injector pump at it????
Try to take a pressure test one last time just for confirmation, after that I guess it’s just time to throw an injector pump at it????
#22
01-02-2018, 07:48 PM
Join Date: Dec 2012
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
My fuel gauge on the smaller shrader valve sucks,uses an adapter. When I finally did get a reading I was sucking air and stalled her out.. I need to get or borrow another gauge.. again the lift pump was new last season, I know , never say never...
Anywho, she is responding to the atf and new filter, not 100% but definitely an intermittent improvement..can stab the throttle and she won’t stall every time, and starting to rev up better...think I am going to add some to the tank or maybe even run a gallon through...
Woo hoo!! fingers crossed.
Anywho, she is responding to the atf and new filter, not 100% but definitely an intermittent improvement..can stab the throttle and she won’t stall every time, and starting to rev up better...think I am going to add some to the tank or maybe even run a gallon through...
Woo hoo!! fingers crossed.
Thread
Thread Starter
Forum
Replies
Last Post
Baddhabit
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
11
01-07-2013 09:25 PM
gummybear918714
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
24
11-09-2011 10:23 AM
BubbaBud
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
7
09-26-2007 10:19 PM