Hi all, I’ll be providing all the details I have on an Engine Light problem I’m having on my 2002 Mazda Tribute (automatic).
I got this car for $2000 2 years back and it’s been super reliable, never broke down. I’m tight on cash so I really want to keep this running.
If I clear the codes and start the car twice, the engine light comes on immediately. Don’t have to drive or anything. I wonder if that’s a hint to the problem.
I’ve taken the car to 3 mechanics (all reliable) 7 times total and no dice. The 6th visit the mechanic told me it’s the ECU/PCM. I replaced it and I’m still getting the same codes.
Here are some screenshots of some OBD scans (and vehicle info): Image 1 Image 2
At the last visit, the mechanic gave me some things to try fixing but I’m skeptical (he didn’t seem too confident in what the issue might be). I would give up now as I’m losing my faith in mechanics, but I figured I would try this sub before throwing in the towel.
Here are my notes I was trying to grab while he was talking (a lot of it is probably nonsense):
EGR sensor on the differential
replace gas cap get from dealer
parking switch (code: ) neutral?
neutral safety switch on the transmission is broken. might be outside the car?
replace sensor on differential
transmission sensor
Here are some things that we’re fixed in the past:
ECU/PCM as mentioned
ABS Sensor
Coil?
Spark plugs
And some other odds and ends that two mechanics failed to give me details on.
As for physical symptoms:
It seems to give a kick sometimes while driving, though not very often.
It can rev high on ignition sometimes.
I think I’ve noticed when driving at low RPMs there’s a rattling noise.
And at high RPMs there’s a whiny noise.
Car shifts a decent amount when parked on a slope.
Parking break doesn’t seem to do anything (besides light on dash).
I’m based in Rockland County New York. I would need to find a really solid mechanic (or someone that just really knows their stuff) to stop me from giving up as I really don’t want to shell out for a new car or lease. Or maybe some solid advice (or words of encouragement) from you guys.
Would a Mazda dealership be a better place to go to? This car is basically a Ford Escape from what I understand.
Please let me know if I left out some crucial information. I’m willing to work on the car myself if someone can point me in the right direction.
Seems an unlikely cause for these symptoms, as you’ve discovered.
The first thing I’d suggest is to ask your shop to identify & post here which readiness monitors are not in the proper “ready” state, and which ones are. Readiness monitors tend to cause a lot of confusion and headaches for the car owner, so expect to have to deal with that, remain calm & don’t give up until you have that list. The reason I suggest this is a good place to start isn’t that it will likely lead to the cause, but it should be relatively easy (i.e. less expensive) to do & may provide some clues on the cheap.
The symptoms could be caused by more than one problem, but appear to be mostly consistent with an EGR system problem. That’s a part of the emissions system, and when a fault is detected in that system the check engine light on the dashboard must turn on to alert the owner, this I believe is required by federal regulations. So there’s no getting around it, the problem has to be fixed. EGR problems can cause stalling, and overall poor engine performance, so it is to you benefit to fix in any event.
I’m just a diy’er w/no experience with your car, and no experience at all with diesels. Suggest to take my comments as mere knucklehead ideas, rather than the expert advice you’d get at a good shop. Knuckleheads btw are encouraged to post here … lol …
All that said, the egr systems on newer diesels are not that much different than on older gasoline engines. If my gasoline-engine Corolla had these symptoms the first test would be whether or not opening the EGR would stall the engine or not at idle. It should. If it didn’t that would be an important clue. Ask your shop if that would be a good test to start the diagnostic process with.
P1401
P1409
There are open circuits detected in the EGR vacuum control solenoid and EGR DPFE sensor circuits. Inspect for broken wires near those two parts.
If no broken wires are found, you might replace both parts. You would probably need assistance to test the wiring circuits from the PCM to the vacuum solenoid and DPFE sensor.
??? Three reliable and experienced mechanics can’t fix a simple EGR system fault on a common Ford powertrain?
None of those items have anything to do with the fault codes you have.
The DPFE (“delta” or “differential” pressure feedback egr) sensor was a very common failure when there were still a ton of these cars on the road. And the definition of code P1401 tells us that the problem is a voltage input issue, not a mechanical fault. If I were a gambling man (and I certainly am), I would bet $100 that you need a DPFE sensor. If your engine still uses the silicone hoses that go to the sensor replace those as well (from the dealer). Clear the codes and recheck. Maybe the EGR solenoid needs to be replaced, maybe not.
The sensor is located on or near the intake manifold of the engine. The differential is at the back of the car where the axles are and has nothing to do with your problems.
I think you should really find some better mechanics… calling these guys reliable makes me think they work for a quick lube oil change place or something…
As asemaster said, this used to be a few times a week issue some years ago, very common, could almost start ordering parts before opening the hood, (joking, but close)…
I remember those red inner coated DPFE hoses breaking down and blowing the red debris of death into the new sensor making you think the new one was defective… lol
OP, find a professional shop that will give you written estimates with the correct part(s) names so you are not writing them down wrong and getting them mixed up… And a real shop could/would most likely had this fixed and back to you the same day, not taken 3 mechanics 7 times and still not have a clue what is going on and possibly saving you money by not buying parts that have nothing to do with the problem…
Thanks for everyone’s responses. I was confused why this wasn’t the first thing they tried, so I called the first mechanic and he said he replaced the EGR system (including the DPFE sensor).
Here’s an image of the EGR system: Image