The Dreaded Misfire Saga Continues

[subsince77]

OK, I'm back after a very insane few weeks. I decided to give the vacuum gauge another shot, since I never did have a CEL while it was hooked up. I put it on two days ago, and today we drove up to Crested Butte. On the way back, as predicted, as soon as we started downhill and let off the gas a bit, the good ol' CEL started to flash. I was watching the vacuum before, during, and after the incident. Not a wiggle. I was happy that I have now eliminated the valves, but pretty much back to square one as to what the real problem is.

 

My next step is to plug up the egr line, and get a code to read. I should be able to start on that tomorrow afternoon. I have to drive another vehicle to pull a boat tomorrow and the next day, but I'll be in the Subie some too.

 

Oh, my wife watched closely on her trip in the Sub last week. She said that it was very consistent that upon crossing passes (10 or 15 minutes of power up one side, then let off to descend) the light would flash after the crest of the pass. Also, coming through a town after motoring down the highway at 70, same thing. This seems to be very consistent. Power followed by letting up = CEL.

[lostinthe202]

[McDave]

Did you ever find out if your cam and crank sensors were transferred to the new motor?

[subsince77]

Did you ever find out if your cam and crank sensors were transferred to the new motor?

No I didn't. I will email CCR right now.

 

This is from their FAQ page, but I'll email and ask.

 

What do I have to swap over from my old engine?

Your intake manifold, hoses, front pulley, flywheel, motor mounts, alternator, power steering and any other accessory items. Older engines would include carburetor, distributor. You do NOT have to swap water pump, oil pump, timing components, oil pan or valve covers: these are all included with your engine.

[subsince77]

Well, I did the EGR test during our week of silence. I disconnected and plugged the EGR. It took a couple of days and a few trips up the valley to get a CEL, but it finally came on in the predictable fashion. Checked the codes - same as always 0303, 0304. No difference, no other codes.

 

Still don't know about the sensors. Emily never responded, which is a little odd. they usually get right back to me. I will try emailing CCR again, but looking at the quote from the FAQ page, I would think they gave me new cam and crank sensors, wouldn't you?

 

Glad to have the site running - hate the new colors though.

[OB99W]

Well, I did the EGR test during our week of silence. I disconnected and plugged the EGR. It took a couple of days and a few trips up the valley to get a CEL, but it finally came on in the predictable fashion. Checked the codes - same as always 0303, 0304. No difference, no other codes.

Well, it was a long shot, but the "obvious" causes seem to have been already covered.

 

 

Still don't know about the sensors. Emily never responded, which is a little odd. they usually get right back to me. I will try emailing CCR again, but looking at the quote from the FAQ page, I would think they gave me new cam and crank sensors, wouldn't you?

My interpretation is that CCR probably didn't transfer the sensors, but that the ones on the engine aren't necessarily "new".

 

 

Glad to have the site running - hate the new colors though.

I agree -- it's great that the site is back up (and the work getting it there is appreciated), but a color scheme/template similar to the previous one would be easier on the eyes.

[subsince77]

Anyplace to go from here? How would I check those sensors, or would it be worth replacing them?

 

i still think a small piece of black electrical tape strategically placed over the cel might be the ultimate answer.

[FSRBIKER]

Anyplace to go from here? How would I check those sensors, or would it be worth replacing them?

 

i still think a small piece of black electrical tape strategically placed over the cel might be the ultimate answer.

 

 

...or just pull the dash and take the bulb out. Your only problem will be inspection but then you just need to clear the code and hope it doesn't come back on before you get there.

[OB99W]

Well, I did the EGR test during our week of silence. I disconnected and plugged the EGR. It took a couple of days and a few trips up the valley to get a CEL, but it finally came on in the predictable fashion. Checked the codes - same as always 0303, 0304. No difference, no other codes.

On rereading your post -- an inoperative (intentionally or otherwise) EGR valve typically would generate a P0400 code due to the ECU not seeing flow, so getting just the misfire codes is "interesting". I have to give this a bit more thought.

[Mugs]

I did not take the time to read everrones post so if this is a repeat, then ignore. I have a customer who was repeatidly coming into the shop for this same problem, but scoping and probing gave no info. His car never ran bad, just would always throw the code. Upon further investigation, I.I. him coming in once a week, to get his light cleared, I decided (since we were slower then normal) to do a little more than usual investigative work. What I found was the his plug seals were leaking into the well holes and the oil was at time grounding out the plug and or just no letting enough ionizing to go on and this would set the code. I replaced the valve cover gaskets, plug grommets and bolt gromets, the oil soaked plug wires and sent him on his way. He has not been back for that particular issue for some time, I am led to believ this solved the problem. Hope this helps.

[subsince77]

...or just pull the dash and take the bulb out. Your only problem will be inspection but then you just need to clear the code and hope it doesn't come back on before you get there.

I live in a town of 6000. What inspection?

[subsince77]

On rereading your post -- an inoperative (intentionally or otherwise) EGR valve typically would generate a P0400 code due to the ECU not seeing flow, so getting just the misfire codes is "interesting". I have to give this a bit more thought.

 

I don't know anything about this, but I wondered why it didn't throw a code.

[McDave]

...or just pull the dash and take the bulb out. Your only problem will be inspection but then you just need to clear the code and hope it doesn't come back on before you get there.

 

I live in a town of 6000. What inspection?

 

Two reasons not to pull or tape up the bulb. If you do live in an emissions inspection area you will fail anyway because your computer needs up to a week or so to run all the tests and clear all monitors. The inspection station will fail you automatically if the monitors haven't all been reset, even if the light hasn't come back on yet. They're wise to that trick.

 

Second reason it's not a good idea is if/when something else goes wrong the light won't be there to alert you to the problem. You could easily ruin your cats if the problem is bad enough to flash the light continuously and you never see it.

[FSRBIKER]

Dave the computer should reset within 20 miles, that is what my brother has told me and he is a mechanic for Lexus. I did this years ago with my Suby when i would get an occasional misfire code and used a code reader to clear it. I then drove 20 miles and it went right through inspection.

[McDave]

Dave the computer should reset within 20 miles, that is what my brother has told me and he is a mechanic for Lexus. I did this years ago with my Suby when i would get an occasional misfire code and used a code reader to clear it. I then drove 20 miles and it went right through inspection.

I too am a career mechanic and on all makes of cars. Some cars, particularly the older ones reset their monitors, if they even have them, quickly. Others need several warm-up, cool-down, and various driving conditions to reset all their monitors and that can take up to a couple weeks depending on your usage.

 

Then there is the type of inspection that your city/state does. Some just make sure your cel light works and your tailpipe sniffs clean. Others plug into your computer and scan for codes and to make sure all the monitors have been reset. If the monitors haven't been reset they know you've either had recent repairs or you are trying to put one over on them. Fail, come back later.

 

It's still a bad idea for the other reason I explained. What happens when something else goes wrong? Say your O2 sensor gets old and weak. The car still runs fine but since the light doesn't work your only clue there may be a problem is you notice your gas mileage is down. By that point you have been running rich enough for so long that you have possibly damaged your cats. Now you're faced with a very large repair bill on top of the original problem.

 

That's just one example of what could go wrong. There are many many others that will cost you more in the long run than if you had just fixed it right to start with, not to mention all the pollution your car is spewing in the meantime.

Edited September 16, 2008 by McDave

[FSRBIKER]

NJ plugs into and reads the computer so at least my Suby was able to have all sensors reset in 20 miles. It seems like if it is not affecting his cars operation so he could just use a piece of tape if it bothers him and just read the codes say maybe once every two weeks for any other issues.

[McDave]

NJ plugs into and reads the computer so at least my Suby was able to have all sensors reset in 20 miles. It seems like if it is not affecting his cars operation so he could just use a piece of tape if it bothers him and just read the codes say maybe once every two weeks for any other issues.

 

I had a car in the shop last week with a cel. When the light came on they noticed the temp gauge was reading hot too. It turns out the electric cooling fans had blown a fuse and the code was for the "radiator fan circuit". Had that light not come on, chances are they would have overheated the engine bad enough to need major repairs, and it would have happened in less than the week or two it would have taken you to scan for problems. Do/did you scan for problems every week or two?

 

Fix the dang thing right in the first place!

[FSRBIKER]

Why are you yelling? First off my CEL is gone..ok DAD. PS. No I didn't scan every two weeks because I never disconnected my light or taped over it.

 

Now Subsince's is not and we all know it's driving him crazy and he has done a huge amount of things to try and get it to stop coming on to no avail. Why don't you fly out there and fix his car if you are so concerned??

[McDave]

Why are you yelling? First off my CEL is gone..ok DAD. PS. No I didn't scan every two weeks because I never disconnected my light or taped over it.

 

Oh I'm not yelling, yet. I did end my sentence with an ! for emphasis since I seem to be having a hard time getting through to you. Look, if you want to ignore the light on your car, that's your prerogative. But please don't advocate that others here do potentially damaging things to their cars by disabling theirs.

 

Now Subsince's is not and we all know it's driving him crazy and he has done a huge amount of things to try and get it to stop coming on to no avail. Why don't you fly out there and fix his car if you are so concerned??

 

I would if I could. One of the reasons I'm so concerned, other than helping a fellow Suby owner, is that one of these problem cars could roll into my shop any day now and I would like to know what it's going to take to fix it without having to spend a 'huge amount' of time and customer's money. I do this on several forums on various makes of cars to sharpen my own repair skills and to help others in the process.

 

Now can we get back to work and on topic please?

[FSRBIKER]

Oh I'm not yelling, yet. I did end my sentence with an ! for emphasis since I seem to be having a hard time getting through to you. Look, if you want to ignore the light on your car, that's your prerogative. But please don't advocate that others here do potentially damaging things to their cars by disabling theirs.

 

 

 

 

Now can we get back to work and on topic please?

 

I agree we should get back on topic after my reply.:-p

 

You don't have to get through to me, I have been working on cars for 25+ years so I have a good working knowledge of how they work...as do you. Who said i ignored the light? I simply cleared mine when I went for inspection many, many years ago since just like Subsince nothing I had tried up to that point made the light go away permanently and the car runs just fine. Who knows why but the CEL just stopped one day. Subsince also made the suggestion of the tape, I simply said he could unplug the bulb instead...it's HIS CHOICE, not yours, not mine.

 

Let's get back on topic now, Subsince have you check for any type of oil leak as was suggested?

[McDave]

Subsince also made the suggestion of the tape, I simply said he could unplug the bulb instead...it's HIS CHOICE, not yours, not mine.

And I simply explained why his half joking suggestion and your suggestion would be a bad choice.

 

I'm going to refer back to my post #62. I went through the database again to see if there were any updates. 95% of the Fixes still point to valvetrain problems such as too tight valve clearance. I had hoped that we could rule that out with a vacuum gauge test, and we probably can.

 

The other 5% were solved with a cam and crank sensor change. Remember though, this was a recall item and the sensors were sold as a pair for less than either separately. Chances are this was done first to most cars before the techs started looking for other causes of the 303, 304 misfire combo, so the actual cures are likely a much higher percentage.

 

As far as the ecm not setting a P0400 code for the disconnected egr, this doesn't concern me too much. Many many times ecms do not set codes that they should, and if/when they do it may take a long time before they do, particularly on early OBD II cars and particularly on early OBD II import cars (GM was way ahead of the other makes back then as OBD II was mostly based on their system).

 

If it were my car, I would do what was easiest and cheapest first. The c/c sensors may not be cheaper than valve cover gaskets, but would be easier to change than checking and re-shimming the valve clearance, and would actually make more sense based on the vacuum gauge tests and the recall of those parts.

 

PS While changing the sensors take a very close look at the connectors looking for corroded, bent, or pushed out pins. Consider doing the same at the ecm if you haven't already.

Edited September 16, 2008 by McDave

[subsince77]

Two reasons not to pull or tape up the bulb. If you do live in an emissions inspection area you will fail anyway because your computer needs up to a week or so to run all the tests and clear all monitors. The inspection station will fail you automatically if the monitors haven't all been reset, even if the light hasn't come back on yet. They're wise to that trick.

 

Second reason it's not a good idea is if/when something else goes wrong the light won't be there to alert you to the problem. You could easily ruin your cats if the problem is bad enough to flash the light continuously and you never see it.

Oh yeah, I was just kidding. I wrote that first sentence before I read the rest of the posts. The rest is an edit - Guys, Guys, I was only kidding. No reason to get anyone's hackles up. I could never tape over the light, first because it would mask a different and potentially serious problem, but also because It would drive me nuts not knowing if it was on. Sorry - only kidding. That is why I put a big grin at the end of that post.

 

I have no oil leaks anywhere around the plugs. Again, new heads, new valve cover gaskets, maybe new plug seals, but anyway, no oil in or around the plugs. No oily plug wires, no leaks anywhere - never uses oil. But good thought. I have had the plugs in and out enough I would have noticed.

 

At some point, if everyone just gets tired of this, we can drop the whole thing and I'll just reset the cel once in a while. It will bug me, but we have gone through a lot of possibilities, No one could say we didn't try and try hard.

Edited September 16, 2008 by subsince77

[McDave]

I haven't given up. It's not in my vocabulary in this bidness.

[forester2002s]

Heck NO! Don't discontinue this discussion!

I open this thread first, each time I log on.

And as for that recent 'black' week, well, I was in withdrawal!

 

From my memory, from a long time ago, in another age, with another car, here is another idea:

I once had a hairline crack in a spark-plug's porcelain insulator. It took me ages to debug. I was actually getting a physical misfire (which I don't think that you have).

But could a cracked insulator set a misfire code??

[subsince77]

Heck NO! Don't discontinue this discussion!

I open this thread first, each time I log on.

And as for that recent 'black' week, well, I was in withdrawal!

 

From my memory, from a long time ago, in another age, with another car, here is another idea:

I once had a hairline crack in a spark-plug's porcelain insulator. It took me ages to debug. I was actually getting a physical misfire (which I don't think that you have).

But could a cracked insulator set a misfire code??

 

I've had this problem through, oh, at least 4 sets of plugs and three sets of wires.

 

So, is the current thought to go ahead and replace some sensors as per McDaves last post? I wonder if I should think about just having the valves set. I can't do that myself, so it is a bit expensive on this car. The people in town hate doing it so they charge big. These valves were presumably set right at CCR 10,000 miles ago, and the sensors are probably not the same ones as the old engine with the same problem - I need to verify that. it may require a phone call, but I'll email one more time.

 

See, that's what hangs me up about this is that the problem is identical to before the engine swap. It did seem to get a little more frequent during the warm part of summer (that's about two weeks in Gunnison). Now it happens about every two weeks or so.