97 expo dont run right

[strokin393]

Ok, I got a 97 expedition that has no cats and non foulers in the rear with all 4 02 sensors hooked up and won't stay running, but with them unhooked, the truck stays running for awhile but not good. The exhaust is cut near the muffler so that's not hooked up. The cel don't work and trucks not on road to drive to parts store to get tested and I wouldn't be able to drive it anyway because it don't run right. I think the 02's are bad, but could be wrong.
Anyone have any ideas?
Update: truck runs a whole lot better and stays running, but not to good. I unhooked the passenger side injectors 1 by 1 and truck ran the same with no difference. I did same to driver side and truck idled down like it should, so the passenger side injectors or coilpacks are all bacd or somethings up. What should I do? What could be wrong? Thanks

 

[strokin393]

It idles real real low around 500 or less before it cuts off. What could be causing the truck to do this? I checked the vac lines, cleaned tb, cleaned mass air, changed fuel filter, plugs, fuel pump, and the air filter.

 

[alexhozee]

Did you check the DPFE and the EGR valve??

 

[strokin393]

Did you check the DPFE and the EGR valve??

How do I check, test, and know if they are bad? I think my DPFE makes a noise when I shut truck off of when it shuts off by itself and don't know if it should be making a sizzle type noise or something

 

[alexhozee]

When you shut down your truck the EGR is making a sound, thats the vacuum coming of the system.

EGR valve check- running engine, put a hose on the vacuum connection on top of the valve and suck on it. You will notice that the truck is going for a rough idle or will die. If so that works.
Engine of. Suck on the hose again and release vcauum at once, you will hear the valve shut down.

EVR- EGR Vacuum Regulator, left of the DPFE, black with two vacuumlines and a elec. connector. Disconnect the elec. connector and check the resistance, it should be between 30 and 70 Ohms.

DPFE- check the lines coming from the EGR pipe, mine were slowly falling apart from the inside and all went up the ref and signal lines into the DPFE.
With running engine put a small safety pin/needle parallel to the elec. wire into the connector. ( Don't damage the wires!!)
Top one is the ref. signal, middle ground, bottom is signal.
Between ground and signal there should be around 5 volts.
Ground and ref should be 0.2-.07 volts ( aluminum DPFE ) around 1.0 volts ( plastic DPFE) with colde engine, that means NO EGR.
When engine is warm, I believe there should be 5 volts with EGR activated.

I replaced my DPFE yesterday, code P1401. After a lot of testing turned out to be DPFE, no faultcode yet.
First the engine would go rough ilde and lack of power cold and warm.
At the moment the engine is doing great at cold engine but when it's hot he will hesitate when accelerating. So I'm noty done yet, but coming there.
hope my english is readable for you.

Good luck!!!!!!!!!

 

[alexhozee]

When you shut down your truck the EGR is making a sound, thats the vacuum coming of the system.

EGR valve check- running engine, put a hose on the vacuum connection on top of the valve and suck on it. You will notice that the truck is going for a rough idle or will die. If so that works.
Engine of. Suck on the hose again and release vcauum at once, you will hear the valve shut down.

EVR- EGR Vacuum Regulator, left of the DPFE, black with two vacuumlines and a elec. connector. Disconnect the elec. connector and check the resistance, it should be between 30 and 70 Ohms.

DPFE- check the lines coming from the EGR pipe, mine were slowly falling apart from the inside and all went up the ref and signal lines into the DPFE.
With running engine put a small safety pin/needle parallel to the elec. wire into the connector. ( Don't damage the wires!!)
Top one is the ref. signal, middle ground, bottom is signal.
Between ground and signal there should be around 5 volts.
Ground and ref should be 0.2-.07 volts ( aluminum DPFE ) around 1.0 volts ( plastic DPFE) with colde engine, that means NO EGR.
When engine is warm, I believe there should be 5 volts with EGR activated.

I replaced my DPFE yesterday, code P1401. After a lot of testing turned out to be DPFE, no faultcode yet.
First the engine would go rough ilde and lack of power cold and warm.
At the moment the engine is doing great at cold engine but when it's hot he will hesitate when accelerating. So I'm noty done yet, but coming there.
hope my english is readable for you.

Good luck!!!!!!!!!

 

[strokin393]

When you shut down your truck the EGR is making a sound, thats the vacuum coming of the system.

EGR valve check- running engine, put a hose on the vacuum connection on top of the valve and suck on it. You will notice that the truck is going for a rough idle or will die. If so that works.
Engine of. Suck on the hose again and release vcauum at once, you will hear the valve shut down.

EVR- EGR Vacuum Regulator, left of the DPFE, black with two vacuumlines and a elec. connector. Disconnect the elec. connector and check the resistance, it should be between 30 and 70 Ohms.

DPFE- check the lines coming from the EGR pipe, mine were slowly falling apart from the inside and all went up the ref and signal lines into the DPFE.
With running engine put a small safety pin/needle parallel to the elec. wire into the connector. ( Don't damage the wires!!)
Top one is the ref. signal, middle ground, bottom is signal.
Between ground and signal there should be around 5 volts.
Ground and ref should be 0.2-.07 volts ( aluminum DPFE ) around 1.0 volts ( plastic DPFE) with colde engine, that means NO EGR.
When engine is warm, I believe there should be 5 volts with EGR activated.

I replaced my DPFE yesterday, code P1401. After a lot of testing turned out to be DPFE, no faultcode yet.
First the engine would go rough ilde and lack of power cold and warm.
At the moment the engine is doing great at cold engine but when it's hot he will hesitate when accelerating. So I'm noty done yet, but coming there.
hope my english is readable for you.

Good luck!!!!!!!!!

I don't have a volt meter on hand, but friend might test for me. I'll try to test egr soon and see if its working. Thanks

 

[AaronLG]

go to the site in my sig. all the guys that know the answers left this site and now are on that one.

 

[strokin393]

I just changed the DPFE and the idle air control valve or whatever its called. The truck runs a little better and longer before it idles down to 500 and sounds like it loading up then I had to shut it off. I haven't checked the EGR yet. I just want to get this thing running so we can see if anything else is wrong with it like the tranny or anything.

 

[strokin393]

I just changed the DPFE and the idle air control valve or whatever its called. The truck runs a little better and longer before it idles down to 500 and sounds like it loading up then I had to shut it off. I haven't checked the EGR yet. I just want to get this thing running so we can see if anything else is wrong with it like the tranny or anything.

It also seems like it doesn't want to run when I try to move it around in driveway. The exhaust is cut right before the back 02's but I had it to where the pipe slides into one another until I can take it to get welded and its cut off before the muffler. Don't think this would effect anything, would it?

 

[markanthony]

IMO. You are dealing with the rear aftermath of the gutted cats. The o2's are reading to much fuel, and not sending fuel into the system. This would be the cause to the low rpm.
I also think. The exhaust has some back pressure in it. If their is not enough or none at all. It wont run right. I would hook up the complete system while running the truck. This just helps take one thing out of the problem.
my steps would be..
1. hook up exhaust complete
2. pull o2's and soak the ends in a bat of paint thinner.
3. check fuel filter, fuel line pressure. (their should be a valve on the fuel rail. if fuel squirts out while key on. their is good enough pressure.)
4. pull o2's out of bat and let dry... bout an hour.
5. install o2's.
6. look to see if their may be a blockage in the last part of the exhaust.

I would think the main reason the truck does not move around is from the engine not running right.

I would also start to think that the engine could have a bigger problem. Like a bad head gasket, or a head problem....

 

[strokin393]

Ok, had truck running and ran a whole lot better it has no codes and don't know why. Check engine light don't come on. I unhooked injectors one by one on passenger side and truck ran no diff and I did same on driver side and it did what it should do, idle down. What could be wrong with the truck??? What should I do or test and how? Thanks

Anyone know how to tell if its the injectors that are all bad on that side or the coilpacks? How would I know which one it is so I can replace either the injectors or packs? Could something be crossed or anything? What should I check and how?

 

[strokin393]

Ok, had truck running and ran a whole lot better it has no codes and don't know way. Check engine light don't come on. I unhooked injectors one by one on passenger side and truck ran no diff and I did same on driver side and it did what it should do, idle down. What could be wrong with the truck??? What should I do or test and how? Thanks

how do I test the coilpacks as well?

 

[strokin393]

how do I test the coilpacks as well?

How do I tell if its the injectors or the coilpacks or whatever it is that's not working on the passenger side? Thanks

 

[strokin393]

Anyone know? I'm going to mess with it on Sunday

 

[strokin393]

Anyone? Could the 02 sensor on pass side be bad and making it run like this and not run any dif when you unhook each injector on that side? Anyone know? Please help before I go blow money on parts I don't need

 

[strokin393]

Ok I change the 4 injectors on pass side and still running like shit. I need a little help here. What could it be? I unhook the pass side injectors and still run same with no change driverside idles down when I unhook. It back fires when I start it. Its not burning gas I think. Coil packs might be dead even the one new one on pass side. What do I do? How do I test?
Ok I took a coil pack from driver side and put on pass side and still the same. Wonder if its getting juice/spark on pass side or can the 02 sensor make it run like that and when I unhook the injectors it don't run and diff but it does when I do drive side. Please give me some kind of idea what it could be.

 

[strokin393]

Why would there be oily gas all in pass side exhaust? Its pretty bad. I took 1st plug out and it was just covered in gas clean gas.

 

[markanthony]

it is sounding like their may be something else bigger going on.. Like a bad head gasket on the passenger side. get a compression gauge and check the compression.. For a rough figure. 100 psi is a good start. if its more then 100 psi and close to equal. if just one is below 100 one just is below. Then I am saying bad rings or so.. I would work the that. See what they do..

After that. I would go for something like bad pcv valve or some blow by from some were. This would be easy to check. unhook the pcv valve hose from the intake side, or other from the intake. if their is some blue smoke that blows out from ANY of the hoses. their is blow by..

 

[strokin393]

it is sounding like their may be something else bigger going on.. Like a bad head gasket on the passenger side. get a compression gauge and check the compression.. For a rough figure. 100 psi is a good start. if its more then 100 psi and close to equal. if just one is below 100 one just is below. Then I am saying bad rings or so.. I would work the that. See what they do..

After that. I would go for something like bad pcv valve or some blow by from some were. This would be easy to check. unhook the pcv valve hose from the intake side, or other from the intake. if their is some blue smoke that blows out from ANY of the hoses. their is blow by..

I hope its not a head gasket. I don't see water or anything in the oil. Could bad 02's make it do all this?