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Check Engine Light

For years, intermittently, my Check Engine Light was on steady. The Ford dealer tried four times (at a cost to me of nearly $400) but was never able to fix the problem. I was always able to get it smogged because I took it in during those periods when the light was functioning normally. But now I’ve got to get the car smogged again and the light is dead. Could be the bulb or something else. Should I take it to an electric shop or a regular mechanic? I understand that CEL issues are common to Fords of this vintage, but the Ford dealers haven’t been helpful.

Does the light come on when you first start the car? I’m pretty sure it should. If it does not, it could be the bulb.
When they do emission tests, they have a way to turn the light on to make sure that part of the system is working.

Has anyone checked to see if there is any error codes (CELs) ? If so what were the codes?

Check Engine Light was on.

That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

Fords are no more prone to CELs than anything else.

Without knowing the year model, engine type, and what codes are present it’s impossible to make a guess about what’s going on.

If the CEL is not illuminating when the key is turned to the RUN position then either the bulb is burned out, there’s a wire harness or connector fault, or there’s a fault with the ECM.
The best way to determine this is to find the CEL lead at the ECM and ground it. If the light comes on then there’s a fault with the ECM; if not, then the bulb is out or there’s a wire problem. The latter is unlikely.

What year is the vehicle. It should not be (as) hard to address if 1996-present. Before they are a little more difficult to address.

See, I understand it such that the bulb never lights - Not that there’s a code stored and the light it on.
You can’t pass emission with a busted check engine light.

@Marquisman, is that’s what’s going on before we have three pages of conjecture?

It’s a 1995, with the 4.6, dual exhaust. I’ve got 160k on it and the car runs great. I figure the bulb is burned out. Several other dash lights also are out, so I figure that when they’re replacing the CEL they might as well do the others as well. Then, I guess the engine light bulb will be back to glowing full time again. I think a good mechanic should be able to figure it out from there. I’ve had this problem for at least eight years. The car always passes the smog test – very cleanly. It’s just that the CEL has been trouble, and the dealers say all they can do is keep replacing different emission-related parts until maybe the light stays out, but they offer no assurances. Honestly, that’s what two dealers told me. I’m hopeful an independent shop can do better. Thanks.

Personally I’m a bit confused by your description.

A) The CEL was on for years, but the Ford dealer could find no cause. (No codes, no parts replaced; The $400 was for four diagnostics) Question: The light was on when you took it in and it was still on when you got it back? Or, the light was on when you took it in and off when you picked it up. Either way, the Dealer had no explanation?

B) Occasionally the CEL would go off and the car passed the smog test?

C) Now the CEL is off all of the time and some other indicators are off as well?

If this description is roughly true, with no additional information, it sounds like the problem was always with the instrument cluster or wiring and not with the emission controls. The CEL was on even though there was no problem with the engine. Take the car and have it smog tested.

In CT you can’t pass emissions with a busted emission light. Some states allow for that and do test with OBD2 port and/or the classic tailpipe method. Just check before you go.

95 Grand Marquis? Chances are the check engine light isn’t part of an emissions inspection. I don’t believe any state requires a functioning engine light on a pre-1996 car. Likely, the emissions test is a tailpipe and component test, meaning if all the emissions components look like they’re there and the exhaust is clean enough, you’re good to go.

May as well have the instrument cluster pulled and all the bulbs replaced, so you can see everything. Then, when the engine light is on have a reputable local shop diagnose the trouble for you. Post the 3-digit fault codes here as well–someone here will help you.

EDIT: OK, for pre-1996 cars California requires a working light to do the test, but car will still pass a test with light on if the tailpipe readings are passing.

Turns out five dash lights were burned out. Had them replaced. Mechanic got a code telling him that the EGR valve was bad. He replaced it and the CEL stayed off – for a mile. Now it’s back on and he’ll have to re-scan to see what else might be at issue. I feel as if I’m starting down a long, expensive smoggy road. I’m sure the car eventually will pass the test, but it’s gonna cost me. At least my dash lights are good.

What was the 3-digit fault code that prompted your mechanic to replace the EGR valve? I’m thinking 332 but my memory is a bit hazy going back to these cars.

Anyway, if you know the EGR sensor is good (also easily tested), have your mechanic remove the throttle body, then the “elbow” adapter that connects the throttle body to the intake manifold, and he will see the EGR ports that are plugged at three small orifices around the horseshoe shaped passage. Clean them and reassemble and be on your way.

On the older 4.6 Panthers, the code squawking usually translates to “EGR low flow”…That means the exhaust gas tube feeding the valve is plugged up. The early ones were a bear to remove and replace. On later models, the design was improved and the tube made larger and easier to get to.

You can reset the light yourself by disconnecting the battery for 30 seconds. I have done this while waiting in line for an emissions test and it passed no problem…Turn the engine off of course when you disconnect the battery…

That CEL condition takes the computer a little time to evaluate and set.
Even if he just reset the light without replacing the EGR, it would probably take a mile or so to turn back on.
In other words, I doubt your EGR was bad.
They actually rarely go bad - very often, they can just be cleaned out with some throttle body cleaner. It may very well be a vacuum leak or some bad connection somewhere related to the EGR that caused the code to be thrown.

Sounds like your mechanic should have cleaned out the passageways in the manifolds and head for the EGR valve. If the EGR valve is clogged up, the passageways are likely to be plugged up as well.

Yeah, that’s what he’s doing now. He’s cleaning out the passageways and might “decarbonize” the throttle body. He’s had the car five days. It’s never easy getting this car smogged, despite the fact that it always tests clean. It’s all the rigamarole connected to getting the car ready for testing that causes the heartburn. But as I said, at least now all of my burned-out dash lights have been replaced and I no longer need a flashlight to illuminate the speedo. Those five bulbs are going to end up costing me about $100 apiece when I’m done. If I get another 30k miles out of this car I’ll be happy.