Help! Car running rich

[silversnake]

More trips at the pump, gassy sulfur smell when I get on it, car drives sluggish at times, misfires at times are the symptoms I'm having. No codes thrown.

[Motorhead350]

Check your spark plug gap... and plugs in general.

[silversnake]

Check your spark plug gap... and plugs in general.

Plugs were changed less than 10k ago

Yesterday I had a misfires on cyl 2,3,7 today no misfire. 3749937500 I thought maybe it was the o2 sensors does these numbers look correct car has been idling when I too these pic.

[silversnake]

3750137502375033750437505

Using my diagnostic scan tool

[silversnake]

3750137502375033750437505

Using my diagnostic scan tool


STFT2 goes from -3.9 to 3.1%
LTFT2 stays at 3.1%

STFT1 -5.5 to 0.0%
LTFT1 stays at 0.0%

[whitey]

Sulfer smell? Catalytic converters, up stream ones. O2 sensors are causing it to run rich because the cats aren't doing their job.

[silversnake]

Sulfer smell? Catalytic converters, up stream ones. O2 sensors are causing it to run rich because the cats aren't doing their job.


I'm going to replace both upstream o2 sensors in the morning, then have a local muffler shop check out my cats.

[ctrlraven]

Before this all started did you do anything to your car? Any new mods or maintenance? How long would you say this has been going on for (mileage and time frame)?

[silversnake]

37507375083750937510

This was done while the car was parked and idling.

[silversnake]

37512

FRP reads 57psi while parked, is this too high?

[silversnake]

Before this all started did you do anything to your car? Any new mods or maintenance? How long would you say this has been going on for (mileage and time frame)?


Started noticing misfires maybe once a week starting a month ago ,and didn't think anything of it.. Just thought it was bad gas. No mods car is completely stock. Regular oil changes is all really. When I purchased the car 1.5 years ago I did notice the cats 2nd cat. On the pass. Side was replaced. Car has 89,XXXmi

[JoeBoomz]

Rich condition will be caused by faulty injectors, bad o2 sensors or bad MAF. Being that you have fails on cylinders on both sides of the engine I would start by cleaning the MAF or borrowing one from someone nearby if possible to rule it out.

[silversnake]

Rich condition will be caused by faulty injectors, bad o2 sensors or bad MAF. Being that you have fails on cylinders on both sides of the engine I would start by cleaning the MAF or borrowing one from someone nearby if possible to rule it out.


Ill try the maf cleaner as well. Thanks

[whitey]

It could be either o2, but i still think your cats are shot, what caused them to fail? o2's, possibly , just my guess

[silversnake]

I spoke to a guy earlier about the issue I'm having and his first reply was to change my o2 sensors, says he went through the same symptoms... He burned his cats out because the car was running rich. I'm going to try everything you guys mention , and hopefully I'll get it resolve by mid-day tommorrow

[EMAS]

The fuel trims suggest that the car is not running rich. The miss fires suggest an ignition issue. Have you replaced the plug wires and/or coils. What brand spark plugs did you install? A miss fire will give you a fuel smell as the unburnt fuel goes out the tail pipe and it will actuallly cause it to run rich as the O2 sensor only reads the O2 level in the exhaust and a miss fire pumps the exhaust full of O2. The biggest problem is the slight miss fires as one that registers will prevent the computer from enriching the mixture as it will ignore the lean reading from the O2 sensor that follows the miss.

Do not waste your money on new 02 sensors at this point, fix your ignition.

[silversnake]

The fuel trims suggest that the car is not running rich. The miss fires suggest an ignition issue. Have you replaced the plug wires and/or coils. What brand spark plugs did you install? A miss fire will give you a fuel smell as the unburnt fuel goes out the tail pipe and it will actuallly cause it to run rich as the O2 sensor only reads the O2 level in the exhaust and a miss fire pumps the exhaust full of O2. The biggest problem is the slight miss fires as one that registers will prevent the computer from enriching the mixture as it will ignore the lean reading from the O2 sensor that follows the miss.

Do not waste your money on new 02 sensors at this point, fix your ignition.


Haven't changed the coils.. Only the plugs have Been changed. Bought motorcraft brand. Initially I thought was a ignition source that was bad, but after running SCT live link a couple days ago, and discover it missed on cyl 2,3,7 during the test drive. The next day car was running rough and sluggish before a misfire. Note: misfire would usually start when driving up a overpass/bridge and/or pressing down the accelerator while cruising.

[Zack]

Haven't changed the coils.. Only the plugs have Been changed. Bought motorcraft brand. Initially I thought was a ignition source that was bad, but after running SCT live link a couple days ago, and discover it missed on cyl 2,3,7 during the test drive. The next day car was running rough and sluggish before a misfire. Note: misfire would usually start when driving up a overpass/bridge and/or pressing down the accelerator while cruising.

You just described a classic COP problem.

[whitey]

When my cops went bad, that was the exact same story i had. Your not far from my mileage that this happened at either. Motorcraft FTW.

[silversnake]

Thanks for the advice guys. I think I might have grew a few gray hairs in the past 72 hours. How much is (8) COP?

[whitey]

I paid 115 i think from a former member on here, but i seen that zack posted a link up in a different post, clintons4 thread for like 200 something. Ill see if i can find it...

[whitey]

Heres a link:

http://mercurymarauder.net/forums/showthread.php?t=91514&page=3

[Zack]

PM clintons04, I think he has a good set

[silversnake]

PM clintons04, I think he has a good set


Thanks just send him PM

[ctrlraven]

New coil sets for sale

http://fordracingparts123.com/electrical-parts/ignition-related/4v-ignition-coil-set-m-12029-4v/?gclid=CMKHi96N4LwCFcY7OgodfwE A3A

http://www.butler-macmaster.com/m-12029-4v.html?gclid=CJrznvCN4LwCFcdQ OgodtDsAGg

[guspech750]

New coil sets for sale

http://fordracingparts123.com/electrical-parts/ignition-related/4v-ignition-coil-set-m-12029-4v/?gclid=CMKHi96N4LwCFcY7OgodfwE A3A

http://www.butler-macmaster.com/m-12029-4v.html?gclid=CJrznvCN4LwCFcdQ OgodtDsAGg

Whoa. That's cheap. Going to order them.


Sent from The White House on taxpayers dimes.

DTR + 4.10's + Eaton swap = Wreeeeeeeeeeeeeeedom

[Limited360]

Thanks for the advice guys. I think I might have grew a few gray hairs in the past 72 hours. How much is (8) COP?


$257 I think is what I paid for 8 of them.

The sulfur smell does point to catalysts as well however. They may have been damaged from misfire and running rich. That being said I also know that a failed catalyst can cause misfire. Sorry to add to the confusion. Personally start with coils, if issues is still present then look to catalysts.

I wonder what the catalyst ratio's look like on that car... Problem is we only monitor our upstream catalysts, so if the downstream fails we have no diagnostic to tell us.


Sent from my iPhone using Tapatalk so I may sound retarded.

[silversnake]

Should I replace just 3 for now. Just Incase it's not the coils. I really want the MSD COIL

[whitey]

All 8, listen to us with going with motorcraft..;)

[guspech750]

All 8, listen to us with going with motorcraft..;)

X 1,000


Sent from The White House on taxpayers dimes.

DTR + 4.10's + Eaton swap = Wreeeeeeeeeeeeeeedom

[silversnake]

All 8, listen to us with going with motorcraft..;)


Motorcraft it is

[silversnake]

Ok orders the COP, there was one more detail I fail to mention is while sitting at a light. When I accelerate it feels like engine has a lot of back pressure. I can smell exhaust with the windows down. Don't hear any whistles or hisses to determine a exhaust leak. Hear a rattle after shifting 1-2 on pass. Side under the car.i took it to the trans. Shop and was told transmission was fine after test driving it and dropping the pan. Could that rattle be the cats

[Limited360]

Ok orders the COP, there was one more detail I fail to mention is while sitting at a light. When I accelerate it feels like engine has a lot of back pressure. I can smell exhaust with the windows down. Don't hear any whistles or hisses to determine a exhaust leak. Hear a rattle after shifting 1-2 on pass. Side under the car.i took it to the trans. Shop and was told transmission was fine after test driving it and dropping the pan. Could that rattle be the cats

A cat will rattle when broken. Go under the car with a rubber mallet and hit the catalyst. Not to hard but enough to shake it. You will hear things moving around... If it makes noise its broken up and this will cause some issues.

However root cause for a broken cat 9 times out of 10 is misfire. Exotherm sky rockets and the substrate cracks! Let us know if you try this out.

[EMAS]

If you have a miss then you are filling the cats with fuel and O2 and it lighting off in the cat can cause some rattling sounds.

Get the ignition fixed first and then if the other problems are still there you can start looking for the cause.

[silversnake]

If you have a miss then you are filling the cats with fuel and O2 and it lighting off in the cat can cause some rattling sounds.

Get the ignition fixed first and then if the other problems are still there you can start looking for the cause.


I ordered the the COP. Pulled the spark plugs and they looks good only 10k on them. About the rattling it's consistent every time car shifts 1-2 I hear it. Drove it to work...I was monitoring all cylinders for misfires using SCT live link. car studder a few times but never registered as a misfire

[silversnake]

First I would like to thank each and everyone of you guys for your input and suggestions on the issues I was having. After reading everyone's comments. I decided to order (8) motorcraft COP's. Borrowed My friend original COP !! PROBLEM SOLVED!😄

[ctrlraven]

Glad you figured out what it was!

[whitey]

Yeah buddy! Zack and emas nailed it, good thing the cats weren't destroyed.

[silversnake]

Yeah buddy! Zack and emas nailed it, good thing the cats weren't destroyed.


They sure did saved me some $$. As for the cats. 3753737538 passenger side didn't make it through the whole ordeal. That's where the rattle I was hearing coming from.

[fastblackmerc]

Should I replace just 3 for now. Just Incase it's not the coils. I really want the MSD COIL


All 8, listen to us with going with motorcraft..;)


X 1,000


Sent from The White House on taxpayers dimes.

DTR + 4.10's + Eaton swap = Wreeeeeeeeeeeeeeedom

Listen to them.... there is a wealth of experience using Motorcraft vs aftermarket. The aftermarkets maybe cheaper but you'll be replacing them again.... and soon.

Replace all 8, yes it's alot of $$'s but if 1, 2 or 3 are bad, how long do you think the other 7, 6 or 5 will last?

[silversnake]

Listen to them.... there is a wealth of experience using Motorcraft vs aftermarket. The aftermarkets maybe cheaper but you'll be replacing them again.... and soon.



Replace all 8, yes it's alot of $$'s but if 1, 2 or 3 are bad, how long do you think the other 7, 6 or 5 will last?


New motorcraft COP ships today should have them in a few days. 37540