Stumbling down the road
Thread Starter
|
New User
Joined: Nov 2006
Posts: 12
Likes: 0
Well I changed the TPS today, reset the computer sart it up and now the engine light is on. Pulled codes on it and TPS is bad (yes the new one). It appears that the stumbling is gone but a new slew of issues. They are oedering me another one at there cost and I will replace it tommorow. I am also replacing the muffler and am curious if there is something othere then stock that you would sugest. It is just an aerostar so nothing to fancy.
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
stock cheap Walker is best...replacements never last as long as original....have welded in if possible....last longer with good welder....
put back all original rubber shock hangers....they are critical to carry the vibration load and not break off the exhaust manifolds...
waste of money to put high performance mufflers on a low performance V6....the large original design passes lots of gas...more than the restrictive 2 into 1 crossover and small cat. converter
also check and replace flex pipe at same time....they are usually shot when muffler goes....get a quality stainless flex inside of stainless mesh...more expensive than the muffer both worth the long life....
check tailpipe also, probably thin and holed at rear end hump or bend
put back all original rubber shock hangers....they are critical to carry the vibration load and not break off the exhaust manifolds...
waste of money to put high performance mufflers on a low performance V6....the large original design passes lots of gas...more than the restrictive 2 into 1 crossover and small cat. converter
also check and replace flex pipe at same time....they are usually shot when muffler goes....get a quality stainless flex inside of stainless mesh...more expensive than the muffer both worth the long life....
check tailpipe also, probably thin and holed at rear end hump or bend
Postmaster
Joined: Apr 2001
Posts: 3,818
Likes: 3
Yep, cheap old Walker Manufacturing cylindrical muffler. $19.99 last time I replaced it....about 70,000 miles ago.... still holding up. Short trips are murder on the exhaust system. No time to warm up and dry out the insides, therefore lots of rust damage.
Thread Starter
|
New User
Joined: Nov 2006
Posts: 12
Likes: 0
Ok, that is exactly what I wanted to know. I have one more question for now, where can I get one of these cheap walker mufflers? Autoparts store, internet, muffler shop. I also think that you guys are right, I need to get a new flex pipe at the same time. Could you also possably tell me what the inlet and outlet diameters are as well as the lenght is on a stock muffler. I hope that these questions are not getting to stupid, just trying to keep the old girl running for as long as I can. Thanks guys for all your help.
Last edited by Luddachris; Dec 7, 2006 at 11:16 AM.
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
http://www.walkerexhaust.com/catalog/vehicletypescrn.asp
shop around....lots of free shipping offers now....try your local discount parts store also....many will match internet pricing and no shipping, may have to wait for part from warehouse
flex unit bolts to back of cat & welds or bell adapter's w. clamps to front of muffler....get new gasket and new bolts....i like stainless steel....can remove or retighten needed
shop around....lots of free shipping offers now....try your local discount parts store also....many will match internet pricing and no shipping, may have to wait for part from warehouse
flex unit bolts to back of cat & welds or bell adapter's w. clamps to front of muffler....get new gasket and new bolts....i like stainless steel....can remove or retighten needed
Last edited by 96_4wdr; Dec 7, 2006 at 02:36 PM.
Thread Starter
|
New User
Joined: Nov 2006
Posts: 12
Likes: 0
Well I got the TPS installed, the check engine light went out but the stumbling it still there. Sometimes it is better and other times it is worse. is there anything else that you guys can think of as why my van would keep doing this. Checked it again for any codes and nothing. Someone told me that there might be 2 O2 sensors on this van but have looked and found nothing. The higher the RPM's the less that it stumbles, however that could just be that I am not feeling it at speed, only on exceleration. Thank you guys for your help, my wife is getting to the point that she thinks that we should just get a new conversion van, but I just can not like the old girl go ( had her to long)
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
is it a stubble/hesitation where engine cuts back?
a miss that cuts in and out?
a surge ahead then cut back?
or continious rough running while accel?
i would run a fuel pressure test while it's stubbling
does it have to be in gear under load on road? or will it accel stubble in park?
marginal fuel pressure from weak pump, plugged pump sock filter or a fuel pressure regulator that has a weakened spring can cause accel. stumble and fuel starvation
will need a long hose commercial fuel pressure gauge that you can monitor in cab
there is a large section in Ford Service cd related to stumble on accel. way too much to cover here
here are the OASIS numbers covered in manual
Hesitation/Stumble 611000
—Acceleration 611500
all OBDI ECU/PCM system Aeros have 1 O2 sensor only, general dividing age is pre '96...a few '95 Aeros are OBDII
one other remote possibility is an excessively worn cam chain/gear set...usually shows up as power loss under load on hills and accel.....
difficult to test for with common DIY test equip....
a miss that cuts in and out?
a surge ahead then cut back?
or continious rough running while accel?
i would run a fuel pressure test while it's stubbling
does it have to be in gear under load on road? or will it accel stubble in park?
marginal fuel pressure from weak pump, plugged pump sock filter or a fuel pressure regulator that has a weakened spring can cause accel. stumble and fuel starvation
will need a long hose commercial fuel pressure gauge that you can monitor in cab
there is a large section in Ford Service cd related to stumble on accel. way too much to cover here
here are the OASIS numbers covered in manual
Hesitation/Stumble 611000
—Acceleration 611500
all OBDI ECU/PCM system Aeros have 1 O2 sensor only, general dividing age is pre '96...a few '95 Aeros are OBDII
one other remote possibility is an excessively worn cam chain/gear set...usually shows up as power loss under load on hills and accel.....
difficult to test for with common DIY test equip....
Lead Driver
Joined: Sep 2003
Posts: 7,013
Likes: 205
From: SoCal
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Thread Starter
|
New User
Joined: Nov 2006
Posts: 12
Likes: 0
I would say that it is a miss that comes and goes, when the engine is cold the miss is very light as the engine warms up it gets worse. On top of that every day is differant, some days it is fine around town you can only notice the miss when getting on the freeway, Some days the miss is so bad that it misses everytime that you touch the gas. It is never the same day to day.
the mechanic that came out here said that he ran a vacume test, so I am assuming that it was done. He said that all was good with vacume.
I am not sure how to run a fuel preasure test.
You asked = does it have to be in gear under load on road? or will it accel stubble in park?
Yes it has to be in gear under a load, I can get it to miss in the drive way if it is in gear and I have the brakes on.
Where can I get a fuel preasure guage to run this test?
You also mentioned a Ford Service cd, where can i get one of those
the mechanic that came out here said that he ran a vacume test, so I am assuming that it was done. He said that all was good with vacume.
I am not sure how to run a fuel preasure test.
You asked = does it have to be in gear under load on road? or will it accel stubble in park?
Yes it has to be in gear under a load, I can get it to miss in the drive way if it is in gear and I have the brakes on.
Where can I get a fuel preasure guage to run this test?
You also mentioned a Ford Service cd, where can i get one of those
Lead Driver
Joined: Sep 2003
Posts: 7,013
Likes: 205
From: SoCal
You might do your own test with a simple vacuum guage, and attach it to one of the intake manifold nipples. It should read at least 18" Hg, but higher the better.
I got my fuel pressure guage from BBK (now Brother's Performance) in Corona, CA. You should be able to find one from other sources. You screw it onto the Schrader valve on the fuel rail to read, and remove when done. The fuel pressure should be around mid to high 30's PSI at idle, and low to mid 40's with the vacuum line removed from the fuel pressure regulator (and plugged so it doesn't upset the engine too much).
You can get images of the Ford service CD's from www.fordcds.com . I had no luck with the 1992 ISO file; I ended up downloading the .NRG file and using Nero to burn it to a CD. It turned out that none of my CD burning software were able to read the 1992 .ISO file, butthey all were able to read the .NRG file.
I got my fuel pressure guage from BBK (now Brother's Performance) in Corona, CA. You should be able to find one from other sources. You screw it onto the Schrader valve on the fuel rail to read, and remove when done. The fuel pressure should be around mid to high 30's PSI at idle, and low to mid 40's with the vacuum line removed from the fuel pressure regulator (and plugged so it doesn't upset the engine too much).
You can get images of the Ford service CD's from www.fordcds.com . I had no luck with the 1992 ISO file; I ended up downloading the .NRG file and using Nero to burn it to a CD. It turned out that none of my CD burning software were able to read the 1992 .ISO file, butthey all were able to read the .NRG file.
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
also Lud,
the vacuum LEAK test we have been talking about looks for vacuum leaks in the throttle body , plenum and intake manifold gaskets from lose bolts or gasket blowout usually caused by backfires
use a spray can of TB, carb, fuel injection cleaner with spray tube...with engine running spray along gasket areas moving very slowly...engine speed up and smooth out=gasket leak
we alway start with bolt torquing to specs and if still leaks=gasket replacement.....common problem on Aero's especially the 4L
the miss/stumble you describe can also be caused by the EGR valve...i show conflicting info that Aero 4.0Ls from '91 on were equiped with EGR...my '96 4L has EGR with DPFE....EGR systems can be difficult to troubleshoot especially an intermittent problem
there is an extensive section on EGR in the Ford Service cd...troubleshooting and repair
the vacuum LEAK test we have been talking about looks for vacuum leaks in the throttle body , plenum and intake manifold gaskets from lose bolts or gasket blowout usually caused by backfires
use a spray can of TB, carb, fuel injection cleaner with spray tube...with engine running spray along gasket areas moving very slowly...engine speed up and smooth out=gasket leak
we alway start with bolt torquing to specs and if still leaks=gasket replacement.....common problem on Aero's especially the 4L
the miss/stumble you describe can also be caused by the EGR valve...i show conflicting info that Aero 4.0Ls from '91 on were equiped with EGR...my '96 4L has EGR with DPFE....EGR systems can be difficult to troubleshoot especially an intermittent problem
there is an extensive section on EGR in the Ford Service cd...troubleshooting and repair
Last edited by 96_4wdr; Dec 9, 2006 at 09:55 PM.
Thread
Thread Starter
Forum
Replies
Last Post
Biggyniner
1968-Present E-Series Van/Cutaway/Chassis
2
Apr 12, 2016 09:31 AM
MTNTIME
1999 - 2016 Super Duty
2
Dec 3, 2015 02:20 PM