With the pressure drop you see when the car sits, that does point to a possible bad FPR that bleeds off. It also could be 1 or more injectors that don't fully close and the pressure bleeds off there. Does the oil smell of gas after it sits and the fuel pressure drops?
Suburban 454 Issues
- Thread starter BowNisPar
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Trav provided me with a set of new injectors for my 1999 K2500 Suburban. My indy mechanic does NOT allow anyone to bring in their own parts. He is very strict about that....because people bring in inferior parts to him all the time.
I showed him Trav's injector's and the performance data that goes with them, and he was shocked. He quickly agreed to use these new injectors without hesitation.
We placed a bunch of stuff on the truck while he did injectors, including FRP, plugs, cap, rotor, wires, fuel filter, etc. etc. Truck would hesitate and buck. Sometimes it would stall at a light.
Not any more.
I showed him Trav's injector's and the performance data that goes with them, and he was shocked. He quickly agreed to use these new injectors without hesitation.
We placed a bunch of stuff on the truck while he did injectors, including FRP, plugs, cap, rotor, wires, fuel filter, etc. etc. Truck would hesitate and buck. Sometimes it would stall at a light.
Not any more.
Originally Posted By: threeputtpar
With the pressure drop you see when the car sits, that does point to a possible bad FPR that bleeds off. It also could be 1 or more injectors that don't fully close and the pressure bleeds off there. Does the oil smell of gas after it sits and the fuel pressure drops?
Yes, the oil does smell like gasoline.
With the pressure drop you see when the car sits, that does point to a possible bad FPR that bleeds off. It also could be 1 or more injectors that don't fully close and the pressure bleeds off there. Does the oil smell of gas after it sits and the fuel pressure drops?
Yes, the oil does smell like gasoline.
Originally Posted By: Phishin
Trav provided me with a set of new injectors for my 1999 K2500 Suburban. My indy mechanic does NOT allow anyone to bring in their own parts. He is very strict about that....because people bring in inferior parts to him all the time.
I showed him Trav's injector's and the performance data that goes with them, and he was shocked. He quickly agreed to use these new injectors without hesitation.
We placed a bunch of stuff on the truck while he did injectors, including FRP, plugs, cap, rotor, wires, fuel filter, etc. etc. Truck would hesitate and buck. Sometimes it would stall at a light.
Not any more.
Awesome, thanks for the info. Trav has been helping me out with the troubleshooting...great guy!
I tried taking off the intake manifold this morning but was thwarted by the EGR tube...the connection is as close to impossible to get off as anything I've dealt with. I can twist the whole thing, but don't want to break the tube. Grr...off to the mechanic tomorrow.
Trav provided me with a set of new injectors for my 1999 K2500 Suburban. My indy mechanic does NOT allow anyone to bring in their own parts. He is very strict about that....because people bring in inferior parts to him all the time.
I showed him Trav's injector's and the performance data that goes with them, and he was shocked. He quickly agreed to use these new injectors without hesitation.
We placed a bunch of stuff on the truck while he did injectors, including FRP, plugs, cap, rotor, wires, fuel filter, etc. etc. Truck would hesitate and buck. Sometimes it would stall at a light.
Not any more.
Awesome, thanks for the info. Trav has been helping me out with the troubleshooting...great guy!
I tried taking off the intake manifold this morning but was thwarted by the EGR tube...the connection is as close to impossible to get off as anything I've dealt with. I can twist the whole thing, but don't want to break the tube. Grr...off to the mechanic tomorrow.
The fact that fuel pressure leaks down with the key off is definitely a problem - it shouldn't do that.
I agree that if extra fuel is leaking into the intake or through a leaky injector, it would cause problems with the learning of fuel trims. Since the leak wouldn't track consistently with injector opening times, the ECM's confusion might produce a scenario where it ends up lean.
An alternate way to test for a leak at the fuel pressure regulator is to just suck on the hose and see if any fuel comes out. It should be sealed tight. Be careful, of course. Some other source of suction that isn't your mouth would be preferred.
I'm bothered by the question of how disconnecting the EGR is affecting this condition, but still, the fuel pressure leak is a real issue in any case. Hopefully fixing that will lead to solving the misfire issue, and it should definitely solve the rich code.
Quote:
When I inspected the EGR, the pintle/plunger had little resistance to being pushed in, but does spring back some. I'm not so familiar with their construction...do you think a broken spring/loose pintle could cause this issue without setting off any lights?
The units I'm familiar with operate on a regulated vacuum, so they'd be checked by sucking on them. It sounds like yours is a stepper motor type, I don't know much about those. Generally though I think of OBD-2 as setting lights very easily.
Anyway, the fuel pressure leak is the best lead. I think you're on the right path to focus on that.
I agree that if extra fuel is leaking into the intake or through a leaky injector, it would cause problems with the learning of fuel trims. Since the leak wouldn't track consistently with injector opening times, the ECM's confusion might produce a scenario where it ends up lean.
An alternate way to test for a leak at the fuel pressure regulator is to just suck on the hose and see if any fuel comes out. It should be sealed tight. Be careful, of course. Some other source of suction that isn't your mouth would be preferred.
I'm bothered by the question of how disconnecting the EGR is affecting this condition, but still, the fuel pressure leak is a real issue in any case. Hopefully fixing that will lead to solving the misfire issue, and it should definitely solve the rich code.
Quote:
When I inspected the EGR, the pintle/plunger had little resistance to being pushed in, but does spring back some. I'm not so familiar with their construction...do you think a broken spring/loose pintle could cause this issue without setting off any lights?
The units I'm familiar with operate on a regulated vacuum, so they'd be checked by sucking on them. It sounds like yours is a stepper motor type, I don't know much about those. Generally though I think of OBD-2 as setting lights very easily.
Anyway, the fuel pressure leak is the best lead. I think you're on the right path to focus on that.
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
Originally Posted By: wtd
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
These seem impossibly cheap. I don't remember the exact figure I paid Trav for his matched set of injectors, but it wasn't this cheap.
Trav, you want to chime in here? Trav is a stand up guy, so I'm sure there is a reason why his injectors are much better than these.
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
These seem impossibly cheap. I don't remember the exact figure I paid Trav for his matched set of injectors, but it wasn't this cheap.
Trav, you want to chime in here? Trav is a stand up guy, so I'm sure there is a reason why his injectors are much better than these.
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Originally Posted By: wtd
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
If they are identical to the ones in the photo, I believe those are stock Ford (Bosch) 19lb/hr injectors from a Crown Vic, F-150....etc.
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
If they are identical to the ones in the photo, I believe those are stock Ford (Bosch) 19lb/hr injectors from a Crown Vic, F-150....etc.
Originally Posted By: Phishin
Originally Posted By: wtd
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
These seem impossibly cheap. I don't remember the exact figure I paid Trav for his matched set of injectors, but it wasn't this cheap.
Trav, you want to chime in here? Trav is a stand up guy, so I'm sure there is a reason why his injectors are much better than these.
Phishin, yours were brand new not cleaned, unfortunately the stock of these is long gone.
Ebay sellers for the most part use cores bought in barrels by the pound. The problem with these is there is no way of knowing what mileage they have one them or even if any came from the same engine.
I don't buy bulk cores i get them known low mile engines that are still wet. Cores of this caliber cost a lot more but they produce a better result.
A lot of guys have the machines but only test them static not the whole program, static only is not very good but running them in auto mode results in a lot more units out of spec.
These Ford/Bosch units flow the 19lbs but fit better with a little work of the seats.
I keep a few good ones in stock to match any of the set that isn't within 1% OE is 3%.
Edit: The ebay ones shown are not stainless or rebuilt. there is no such animal with this type of injector. You can only clean them, the bodies are steel and plastic.
Originally Posted By: wtd
Here are the upgraded Bosch injectors that are usually recommended for replacing the stock ones. Looks like everyone is selling remans these days but for the price and a five year warranty, not a bad price to try them out.
http://www.ebay.com/itm/5-Yr-Warranty-Ge...a5c&vxp=mtr
Wayne
These seem impossibly cheap. I don't remember the exact figure I paid Trav for his matched set of injectors, but it wasn't this cheap.
Trav, you want to chime in here? Trav is a stand up guy, so I'm sure there is a reason why his injectors are much better than these.
Phishin, yours were brand new not cleaned, unfortunately the stock of these is long gone.
Ebay sellers for the most part use cores bought in barrels by the pound. The problem with these is there is no way of knowing what mileage they have one them or even if any came from the same engine.
I don't buy bulk cores i get them known low mile engines that are still wet. Cores of this caliber cost a lot more but they produce a better result.
A lot of guys have the machines but only test them static not the whole program, static only is not very good but running them in auto mode results in a lot more units out of spec.
These Ford/Bosch units flow the 19lbs but fit better with a little work of the seats.
I keep a few good ones in stock to match any of the set that isn't within 1% OE is 3%.
Edit: The ebay ones shown are not stainless or rebuilt. there is no such animal with this type of injector. You can only clean them, the bodies are steel and plastic.
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Originally Posted By: BowNisPar
Originally Posted By: threeputtpar
With the pressure drop you see when the car sits, that does point to a possible bad FPR that bleeds off. It also could be 1 or more injectors that don't fully close and the pressure bleeds off there. Does the oil smell of gas after it sits and the fuel pressure drops?
Yes, the oil does smell like gasoline.
Now we're getting somewhere. That tells me that you have fuel getting into the oil somehow, likely the FPR leaking into the vacuum hose that gets into the intake somewhere or injector(s) leaking directly into the cylinder and down the walls.
Go with the suggestion of putting vacuum on the hose that attaches to the FPR and see if it pulls fuel out. Use a vacuum hand pump unless you really like the taste of 87 octane. If no fuel comes out at 18 hG, then it's one or more of the injectors.
If it turns out to be injectors, then the question is whether or not the stumble is annoying enough to fork out the cost of 8 new injectors. Or you could buy one or two and just start swaping them one at a time until you find the leaking one(s).
Originally Posted By: threeputtpar
With the pressure drop you see when the car sits, that does point to a possible bad FPR that bleeds off. It also could be 1 or more injectors that don't fully close and the pressure bleeds off there. Does the oil smell of gas after it sits and the fuel pressure drops?
Yes, the oil does smell like gasoline.
Now we're getting somewhere. That tells me that you have fuel getting into the oil somehow, likely the FPR leaking into the vacuum hose that gets into the intake somewhere or injector(s) leaking directly into the cylinder and down the walls.
Go with the suggestion of putting vacuum on the hose that attaches to the FPR and see if it pulls fuel out. Use a vacuum hand pump unless you really like the taste of 87 octane. If no fuel comes out at 18 hG, then it's one or more of the injectors.
If it turns out to be injectors, then the question is whether or not the stumble is annoying enough to fork out the cost of 8 new injectors. Or you could buy one or two and just start swaping them one at a time until you find the leaking one(s).
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I remember a few years ago, Ebay had some of the brand new Bosch injectors for around $289 shipped. I almost bought some for my 98 K3500 but didn't and now I wish I had.
My truck still runs pretty good but idles kind of rough. I also don't seem to be getting any leak down of the fuel because the truck always starts right up even when it sits for a long period of time so I'm guessing my injectors are still good.
Wayne
My truck still runs pretty good but idles kind of rough. I also don't seem to be getting any leak down of the fuel because the truck always starts right up even when it sits for a long period of time so I'm guessing my injectors are still good.
Wayne
Here is a new set of Bosch injectors that are a lot more expensive than the ones I listed before.
http://www.ebay.com/itm/8-Bosch-Gen-III-Fuel-Injectors-Chevy-GM-7-4-454cid-OEM-Upgrade-NEW-Add-HP-Torque/371143430022?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D29385%26meid%3D169684e91bd34f02807f479a870d7569%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D190867917009&rt=nc
Wayne
http://www.ebay.com/itm/8-Bosch-Gen-III-Fuel-Injectors-Chevy-GM-7-4-454cid-OEM-Upgrade-NEW-Add-HP-Torque/371143430022?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D29385%26meid%3D169684e91bd34f02807f479a870d7569%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D190867917009&rt=nc
Wayne
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I cant say all ebay sellers are selling this sort of stuff but its very common.
He is a real Denso injector and a Made in China being sold on by the set on ebay for cheaper than they cost wholesale for one.
They were sent to me for diagnosis.
Genuine OE Denso. Notice the green top.
Fake Denso, yes the color is really that far off and Denso is not in the correct location. OE comes in plastic vacuum bag the fakes come wrapped in paper in a box.
Some knock offs look better than this scrap but all are inferior to the original.
This is the damage done when they put the filter in with a hammer.
This is one company they get them from. Any brand and # you ask for a few $ ea
http://www.creditparts.cn/productgrouplist-209345101/Fuel_injector.html
He is a real Denso injector and a Made in China being sold on by the set on ebay for cheaper than they cost wholesale for one.
They were sent to me for diagnosis.
Genuine OE Denso. Notice the green top.
Fake Denso, yes the color is really that far off and Denso is not in the correct location. OE comes in plastic vacuum bag the fakes come wrapped in paper in a box.
Some knock offs look better than this scrap but all are inferior to the original.
This is the damage done when they put the filter in with a hammer.
This is one company they get them from. Any brand and # you ask for a few $ ea
http://www.creditparts.cn/productgrouplist-209345101/Fuel_injector.html
Trav hooked me up big time. He flow tests them and makes sure they're all flowing properly before he ships them, even NIB injectors.
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