EGR system vacuum hoses
Thread Starter
|
New User
Joined: Jun 2006
Posts: 2
Likes: 0
EGR system vacuum hoses
Hey everyone,
I've got a 98 Mazda B4000 4WD with 90K. About a year ago I was getting an EGR code (can't remember the specific) but it alluded to the DPFE sensor. I pop the hood, and low and behold the REF tube coming out of the DPFE sensor was melted and the hose from EGR exhaust tube had nothing to connect to. I was told that it could have gotten clogged with carbon and could have melted. Either way I put in a new DPFE sensor and the truck ran fine, code disappeared.
Now, I am getting a P0402 code (EGR Flow excessive). I pulled off the DPFE and the intakes seem clear. I checked the hoses from the DPFE to the EGR manifold tube and no problems there. I pulled off the EGR Valve and it seemed pretty dirty with some carbon buildup. I hosed it down with carb cleaner and put it back on. The code came back in a day.
I just put a brand new EGR Valve on, and the P0402 code is back. Now I'm thinking that it has something to do with the EGR Vacuum Regulator solenoid or the vacuum hoses. I'm going to check the vacuum hoses to see if they are clogged tonight, and possibly see if I can disassemble the EVR and clean it out.
My question is, could this recurring code be something else that I'm missing? I guess it is possible that I got a crappy DPFE sensor (it is only a year old). Also, where can I get the small vacuum hoses/fittings that connect all of these EGR components (EGR Valve, EVR, and intake manifold)? It looks like a harness type set, but I can't find them on the internet anywhere. Do I have to make a custom set if one of these hoses are clogged or have a hole?
Thanks everyone for your help.
Rich
I've got a 98 Mazda B4000 4WD with 90K. About a year ago I was getting an EGR code (can't remember the specific) but it alluded to the DPFE sensor. I pop the hood, and low and behold the REF tube coming out of the DPFE sensor was melted and the hose from EGR exhaust tube had nothing to connect to. I was told that it could have gotten clogged with carbon and could have melted. Either way I put in a new DPFE sensor and the truck ran fine, code disappeared.
Now, I am getting a P0402 code (EGR Flow excessive). I pulled off the DPFE and the intakes seem clear. I checked the hoses from the DPFE to the EGR manifold tube and no problems there. I pulled off the EGR Valve and it seemed pretty dirty with some carbon buildup. I hosed it down with carb cleaner and put it back on. The code came back in a day.
I just put a brand new EGR Valve on, and the P0402 code is back. Now I'm thinking that it has something to do with the EGR Vacuum Regulator solenoid or the vacuum hoses. I'm going to check the vacuum hoses to see if they are clogged tonight, and possibly see if I can disassemble the EVR and clean it out.
My question is, could this recurring code be something else that I'm missing? I guess it is possible that I got a crappy DPFE sensor (it is only a year old). Also, where can I get the small vacuum hoses/fittings that connect all of these EGR components (EGR Valve, EVR, and intake manifold)? It looks like a harness type set, but I can't find them on the internet anywhere. Do I have to make a custom set if one of these hoses are clogged or have a hole?
Thanks everyone for your help.
Rich
Elder User
Joined: Jul 2005
Posts: 520
Likes: 0
Yes it's possible the DPFE can cause this.
Being you have a new EGR valve, do this. Unplug the vacuum hose at the EGR valve and make sure there's no vacuum on it at idle. If there is vacuum there than most likely the EGR solenoid is sticking. If not then you might want to consider replacing the DPFE again. Make sure you get a Motorcraft one, as it's been redesigned, and a lot of aftermarkets use the old design.
Good luck.
Being you have a new EGR valve, do this. Unplug the vacuum hose at the EGR valve and make sure there's no vacuum on it at idle. If there is vacuum there than most likely the EGR solenoid is sticking. If not then you might want to consider replacing the DPFE again. Make sure you get a Motorcraft one, as it's been redesigned, and a lot of aftermarkets use the old design.
Good luck.
Thread Starter
|
New User
Joined: Jun 2006
Posts: 2
Likes: 0
Question about this new DPFE: how is it different from the old one? I got an Airtex DPFE sensor a little less than a year ago. Still has the plastic housing and all. Is there a way to tell if it is the new one?
And, as a followup, I think that my EVR is clogged. I could feel a little bit of a vacuum on the line from the EVG to the EGR valve, and pulling the EVR off I could blow into both nozzles. I shook it around a bit, cleaned the gunk off of the vent on the top, and put it back in.
I was very surprised to see when I plugged in my code scanner that the code was gone. Now, just removing an EGR part shouldn't remove the code, right? I didn't unhook the battery or clear the code using my reader. I'm just surprised because even when I fix something that is causing the problem, it usually takes a drive cycle or two for the code to clear on its own.
Rich
And, as a followup, I think that my EVR is clogged. I could feel a little bit of a vacuum on the line from the EVG to the EGR valve, and pulling the EVR off I could blow into both nozzles. I shook it around a bit, cleaned the gunk off of the vent on the top, and put it back in.
I was very surprised to see when I plugged in my code scanner that the code was gone. Now, just removing an EGR part shouldn't remove the code, right? I didn't unhook the battery or clear the code using my reader. I'm just surprised because even when I fix something that is causing the problem, it usually takes a drive cycle or two for the code to clear on its own.
Rich
