running rough and strong gas smell

[smitysangel]

I have a 94 Explorer that recently started running really rough with the check engine light coming off and on going down the highway. When you get out you smell a strong gas smell and lately I have noticed when you start it up after running it a while there is a weird smell. Also when sitting at lights or letting idle after warm up of engine it starts to shake really hard. Another thing is that when driving down the road after check engine light goes off is that it begins to surge and also seems to be slow to shift at times. Anyone that has any ideas as to what this is I could sure use your imput. It is the only vehicle I have and need to get to work and kids to school.

 

[section525]

Probably a plug not firing because of A) a bad plug B) a bad wire, or C) a bad coil pack. When was the last time you changed plugs and wires and whats the mileage?

 

[smitysangel]

Have no idea what the mileage is. Put a 91 one engine in the 94 because the 94 was bad. When this was done however their was new plugs and wire put it and that was about 20,000 miles ago

 

[DanShrader]

Did you get the codes yet? I didn't when I had a similar problem and ended up replacing almost all the sensors and the fuel pressure regulator, $200 worth of parts and it ended up that the tempeture sensor (not the one the the guage the one for the ECU) had gone bad. So in the end I spent over $200 and I could have spent $16.

 

[superdave88]

I'm having a similar problem.

I have a 94 Explorer that recently started running really rough with the check engine light coming off and on going down the highway. When you get out you smell a strong gas smell and lately I have noticed when you start it up after running it a while there is a weird smell. Also when sitting at lights or letting idle after warm up of engine it starts to shake really hard. Another thing is that when driving down the road after check engine light goes off is that it begins to surge and also seems to be slow to shift at times. Anyone that has any ideas as to what this is I could sure use your imput. It is the only vehicle I have and need to get to work and kids to school.

I'm new... I'm having a similar problem with the same make and model. It started 6 or more months ago with the surging but, no check engine light. Now it will barely run. I sometimes get a dash light on but not very often. If I hold the accelerator to the floor and start it and the idle shoots up high...(as would be expected) I can throw it it in gear and go but, don't let off of the gas or you have to start all over again. e.g. At stop lights and in traffic. If the idle doesn't shoot up turn off key and try again. If it's (idleing, ideling whatever..) like crap it will be sharp on the accelerator and if it is idleing good it will stall on acceleration. Any way I've replaced the.......fuel pump,fuel filter, MAF,TPS,IAC, and most recently the ignition coil. Still runs like crap!!! The codes come up, Dropping cylinders 1,4,and 5 then Mass Air Flow, Brake On Off something or other, Throttle Positioning out of range or something like that.. O2 sensors, MAP On and on. So I started at the top and had the ignition coil checked. (A resistance check) checked out good. Had the ig. module checked..good. replaced the coil ..No bueno!!!!! I have got to fix my Wife's truck. I'm riding my motorcycle (rain or shine) and she's driving my work van. I'm rambling HELLLPPP!!!!!

 

[Bwana Bob]

Do a search on Fule Pressure Regulator (FPR). Some fuel pressure regulators fail causing fuel to leak from the FPR to the vacuum line that connects it to the vacuum manifold. This will cause the engine to run super rich. Pull the vacuum line off and check for fuel coming out of it. Also, check (using an appropriate gauge) the fuel pressure at the schrader valve. it sould be about 30-35 psi and go up about 5 psi when the vacuum line is disconnected.

Bob

 

[TPLYNCH]

Ditto the fuel pressure regulator. Also, check and make sure all you vacuum lines are connected, none are cracked, and you aren't missing any caps on the vacuum tree ("octopus")

 

[superdave88]

I'm leaning towards EEC or some other electronic issue. It's so intermittant (runs fine runs like diarreah) I've poked and prodded everything. Checked vacuum. The fuel pressure regulator sounds like a good bite though. Maybe the E.E.C. power relay? I'm pulling out my hair... Running out of hair fast... !!!

 

[MrShorty]

I'm leaning towards EEC or some other electronic issue. It's so intermittant (runs fine runs like diarreah) I've poked and prodded everything. Checked vacuum. The fuel pressure regulator sounds like a good bite though. Maybe the E.E.C. power relay? I'm pulling out my hair... Running out of hair fast... !!!

superdave: You said you got a lot of codes when you pulled codes. May I ask, what KOEO codes did you get? What KOER codes did you get? What memory codes were there? SOP is to work on the KOEO codes first.

smitysangel: I would just echo what others have said: pull codes and check the fuel pressure regulator.

 

[superdave88]

Koeo

I finally pulled the codes. Here goes.... 118-Coolant temperature sensor circuit above max. voltage. I disconnected that sensor the other day and it was not reconnected before the test. It seemed to help but, only for a little while. 157-MAF below min. voltage. 214-cylinder identification circuit failure. 327-EGR valve pressure transducer/position sensor circuit below min. voltage. 556-Primary fuel pump circuit failure. I'm lost Maybe the PCM is just trash or something.... I don't know???!!..

 

[MrShorty]

Now that you've given specific code numbers, I'm going to ask: which of those codes are KOEO codes (before separator pulse of KOEO tests), which are KOER codes (from KOER test), and which are continuous memory (CM) codes (after separator pulse during KOEO test). It can make a difference in how you diagnose a code to know which type of code it is. Once you identify which type of code each is, SOP is to resolve the KOEO codes first. One exception might be regarding the CM 214, which points to problems in the ignition system (CKP, ICM, or associated wiring). You've got several codes, and the best way to approach this is to work systematically resolving codes, until you get them all resolved. And it's important to remember that codes only point to circuits, not sensors. The computer can't distinguish between a broken wire, bad ground, or bad sensor.

 

[toad]

I,ll give another vote for FPR, the gas smell really sounds like it, check you oil and see if any gas is getting in it, what happens when it goes is it floods the engine with fuel.
It sound just like what my 92 did when my FPR went.

Todd

 

[Noved87]

my first car had the same problem. check the gaps on the plugs, plugs, and wires. Did you possible overfill the oil? thats what happened to me oil leaked out accidently overfilled. OOPS!!!

 

[502teazy]

I have. 2008 Explorer and as of recent I let my buddy use my truck and every since he tried using my 4wheel drive I’ve been getting a rough ride and it smells like exhaust as well as an annoying loud screeching sound . My gas gauge is also faulting. I had 135 miles to empty. Maybe drove 17miles of it n now it says 26miles to empty and I’ve checked all around under the truck and sense no leakage. All these problems came at the same exact day. Please help on insight. I had my cylinder 3 and 1 plugs changed weeks ago due to a misfire and improper acceleration and it helped. This problem just started occurring days ago.

 

[RangerX]

I have. 2008 Explorer and as of recent I let my buddy use my truck and every since he tried using my 4wheel drive I’ve been getting a rough ride and it smells like exhaust as well as an annoying loud screeching sound . My gas gauge is also faulting. I had 135 miles to empty. Maybe drove 17miles of it n now it says 26miles to empty and I’ve checked all around under the truck and sense no leakage. All these problems came at the same exact day. Please help on insight. I had my cylinder 3 and 1 plugs changed weeks ago due to a misfire and improper acceleration and it helped. This problem just started occurring days ago.

Welcome to the forum!
It would be best if you reposted this as a separate thread, and in the section for your year of Explorer.
This thread was about first generation Explorers, an entirely different animal.

 

[Nadams01]

I have a 94 Explorer that recently started running really rough with the check engine light coming off and on going down the highway. When you get out you smell a strong gas smell and lately I have noticed when you start it up after running it a while there is a weird smell. Also when sitting at lights or letting idle after warm up of engine it starts to shake really hard. Another thing is that when driving down the road after check engine light goes off is that it begins to surge and also seems to be slow to shift at times. Anyone that has any ideas as to what this is I could sure use your imput. It is the only vehicle I have and need to get to work and kids to school.

Its a 94, and OBD1. I would ignore the CEL being intermittent as the computer used for an OBD1 is pretty dim witted. Thankfully we do have some stored codes, the MAF being below voltage is a pretty good direction to start. There are not many sensors used to dictate air fuel mixture. We have MAF, 02 sensor, MAP or Biometric air temp, and a couple of other inputs that are incorporated with each other. If you have a multi-meter, you can read the voltage at idle by taping the blue and brown wires. Blue is positive and brown is negative. At idle you should get .7 volts. You can try cleaning it with special MAF cleaner and replacing the air filter. If that doesn't work, make sure you buy a MAF as a whole assembly, I have had 2 new MAF that were throwing my AFR all out of wack but not bad enough to trip a code so keep that in mind.

 

[Nadams01]

Have no idea what the mileage is. Put a 91 one engine in the 94 because the 94 was bad. When this was done however their was new plugs and wire put it and that was about 20,000 miles ago

Same diagnostic flow applies to you as well. double check voltage at MAF to start, and check that FPR. Check primary resistance in your ignition coil as well, a quick google search will show you how and what Ohms you are looking for.