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Discussion Starter #1
After using sea foam to get rid of my Lean bank 1 code, my truck now runs terrible! I put 1/3 of the can in the intake and the rest in 1/2 tank of fuel. It started running really good! But later that night it started kinda lurching while driving and idled rough. Well that eventually went away so I figured it was just burning off bad fuel or something from the sea foam. But since then it has been wet out and for some strange reason it doesn't idle bad in drive but when you put it in park it idles rough like it's got a big cam! Lol but it's gotten worse like when coming off the freeway last night it bogged down and lost most of it's acceleration and stRyed lurching again. My question is, did sea foam gunk up my intake system causing this? I thought maybe plugs and wires but the previous owner said he just did plugs, wires, cap, and rotor.
 

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The lurching / bogging, etc sounds like a mis-fire. At the very least I would pull the spark plugs and see what they look like....Odds are you fouled a plug or two.
 

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Do you still have the lean bank 1 code? If so I would treat your symptoms as seperate from the sea foam. Sounds as if you have other issues especially with 200k plus.... Don't trust PO. Even if he did a comeplete tune-up, who knows what brand parts he used! Some people think just changin' plugs is considered a tune-up on a computerized vehicle!:doh0715:
 

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Discussion Starter #4
I'll go up to oreillys this morning and read my codes again and see what it's saying. After sea foaming I reset my computer and the CEL stayed off until it started running bad so with any luck it is just a fowler plug. I'll keep you guys updated
 

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keep us posted. I have reservations of sea foam but I guess a fouled plug isn't too bad other htan I just changed mine out.
 

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Wrenching for a Livin'
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Seafoam isn't going to fix a lean code.

If your check engine light is on now, even if it isn't, Def. check for codes first. Fix the issues causing the codes.

It wouldn't be a bad idea to pull the plugs and check them, normally the crap seafoam breaks loose will burn off the plugs after a few miles.
 

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Discussion Starter #7
Well I read the codes. I have 5:

P0171 - system too lean bank 1

P1131 - Lack of H02S11 switches

P1132 - Lack of H02S11 switches

P1130 - Lack of H02S11 switches - fuel trim at limit

P0300 - random misfire


The guy at oriellys said the all the lean codes were a bad o2 sensor and the random misfire is likely cap rotor and wires. He said if it were the plugs the computer would have likely specified the cylinder. I went home and sprayed the cap and wires but everything seemed ok, not arching. Also the PO might have been telling the truth because the cap rotor and wires look pretty new. Could i just have multiple fouled plugs?
 

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They could all be related. Sounds like the O2 sensor is reading a lean condition.(front sensor) Doesn't mean the O2 is bad, but it is possible. As o2s get older they loose the ability to raise voltage, usually the heater goes out before this happens, or is the cause of the issue. Running the engine so lean that it reaches its fuel adaptive limit could definitly cause misfires. Check the heater fuse for the O2 sensor, make sure you are getting power and ground to it.

Normally I would say you could have a vacuum leak or possibly a contaminated Mass Air Flow sensor, but Im not sure if your truck has a mass air sensor or not...could be either/or on your year. If you have a MAP sensor A vacuum leak my mess with the MAP reading, not sure if it would cause a lean condition or not.
 

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Discussion Starter #9
it does have an MAF and ive got cleaner for it and have been meaning to clean it. It might be a stupid question, but an exhaust leak wouldnt cause a lean condition would it? It just seems more than coincidental that since sea foam this misfire has shown up, im still leaning towards the plugs being fouled, ill check those. Also i dont think ive got a vacuum leak, i did the carb cleaner check and everything seemed ok.
 

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Yes, and exhuast leak can cause the o2s to read lean as well. Any exhuast leak BEFORE the O2.

Since you have a maf, check for vacuum leaks for sure, clean the maf with some electronic cleaner(the resistors inside it)

You may have some crap on the plugs, pull the out and clean them off. Like i said most of the time it will burn off fairly quickly. Either way, as long as the plugs are still gapped within spec and aren't worn down/cracked, cleaning them off will be fine.
 

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Discussion Starter #11
Well the exhaust leak is around the seams of the muffler, its been like that since i bought it and ran fine other than the lean issue.

in addition to cleaning the plugs, would cleaning the IAC and or throttle body make a difference??

Ill also re check vacuum leaks later too
 

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If the IAC was causing issue it would idle High/low/not at all. A dirty throttle body would only cause a sticky gas pedal, maybe a off, or slow throttle position reading

the leak at the muffler wouldn't cause any issues.

When checking for vacuum leaks, check for more than just bad or loos lines. Get some carb cleaner and spray around the intake to see if the rpms rise up, if it does, thats where the leak is. A more accurate way would be to use propane and a scan tool to see when the o2 starts reading rich
 

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Discussion Starter #13
ok so i pulled a plug and it looked pretty new still and was clean. I also made sure all the wires were tight. A few weeks ago i tested for vacuum leaks when i was trying to track down the lean issue and everything seemed good.

So basically is the misfire non realted to the sea foam, rather just coincidence??

If I disconnect my MAF and start the truck is that how I can test if its malfunctioning?

Also, where is that heater fuse located to test my o2 sensor?

Btw, thanks for everyones help!
 

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The misfire is most likely due to the excessive lean condition you have.

If your truck idles really rough, and then when you disconnect the maf and it smooths out that is usually a sign that it is going out. Another way to do it is to backprobe the signal wire from the maf(the wire going back to the EEC to tell it how much air is going into the engine) and see if you are getting a steady voltage at idle and that the voltage raises smoothly when revved up.(showing an increase in airflow). A faulty maf will usually have voltages that jump around a good bit.

clean the maf first
 

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Im not sure about the o2 sensor heater fuse...i would think its labeled in the fuse panel...Its possible its tied to the MAF sensor too...they are on some vehicles.
 

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but Im not sure if your truck has a mass air sensor or not...could be either/or on your year.
all ford trucks were MAF by 1996.
 

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magnumpi has been giving you great advice.

If you had a lean code, that got worse with the seafoam, I'd suspect that you have a vacuum leak. Perhaps at the PCV and its grommet.
Where did you disconnect to add the seafoam? I'd look there for a loose connection too.

OTherwise cleaning the MAF is also a good idea.
 

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Discussion Starter #19
So here's where I'm at guys,

I re checked for vacuum leaks but found none

I replaced the Pcv valve, but that didnt change anything

I disconnected the MAF and started the truck and it still missed, so does that mean the MAF is ok?

Basically I'm now leaning towards a bad o2 sensor. It seems the problem got bad after it got really wet out. But driving on the freeway tonight it seemed to be missing slightly but the kind of surged then ran smooth, then later out of nowhere it started shaking pretty good while on the freeway but stopped fairly quick. The big thing I noticed tonight two was it seemed to miss especially bad when in park or neutral and did so when I was letting it warm up but when I put it in park after the drive home it idled pretty smooth for a change! Does that not seem like a faulty sensor to anyone else??
 

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I have been getting lean and rich codes for a year now, P1151 shows up on a regular basis, I just keep clearing it.
I got the fuel limit code once, but my truck has never missed or shuddered like you describe, wierd.
 
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