I just bought a 2001 F150 with a 4.2L engine. Just changed all the spark plugs (Motorola OEM) and spark plug wires (aftermarket, but 8mm), and no change.

When I first bought it, the "Service Engine Soon" light was on, and the "oil pressure gauge" and the oil light would turn on at idle when RPM's fell below 1,000 but after fiddling with the engine one night, wiggling wires and disconnecting and reconnecting stuff (basic exploring my new truck) suddenly, magically the "Service Engine Light" and the oil light went off and have not come back on. No clue what I did to "fix" it.

The engine runs rough, particularly at idle. It shakes around and sounds like it's missing. My first suspicion is the Ignition Control Module, since I had an F150 that ran rough like this and replacing the ICM fixed it.

BUT:

There are two OBD2 codes: P1000 and C1185, which for Fords seems to be related to the ABS system.

The ABS light is on, on the dashboard, but only after it's been driven for a couple of minutes. When the engine first starts, the dashboard lights are all "Off".

The AirBag light is also on. Yellow icon showing seated passenger with a large circle in front of the passenger's face. Assume that's air-bag related. Lower right corner of instrument panel.

So the reason why I titled it asking about the "computer" is that first one of the possible causes for the P1000 code is that the "testing is not complete", plus the on-but-now-off engine oil pressure gauge/light problem, the ABS light and the Air-Bag light and the engine running rough are all non-related, non-connected, symptoms but have the common possible cause of a "computer" somewhere. If the truck even has a computer. IDK.

So those are my two theories:

1) Ignition Control Module isn't firing consistently, or
2) Some "computer" isn't regulating (whatever, fuel, air, fire, IDK) like it's supposed to. Broken ground somewhere?

Is there a way to test the ICM to rule it in or rule it out as the possible cause of the problems? Would a bad ICM cause the other issues?

 

You don't have an ICM, it can't fail and you can't test it.

The computer is extremely unlikely to be the problem. Possible, but there are dozens of better suspects.

A P1000 is completely normal after a battery disconnect until all the self-test monitors are completed.

The C1185 is related to the ABS system only. Tah airbag fault is specific to the airbag system. Neither have anything to do with engine operation or the check engine light you saw.

The oil pressure light is probably a failing pressure switch. It has nothing to do with the check engine light or anything else (unless the engine starts to clatter because it's oil-starved).

The rough running is usually either a vacuum leak or a misfire.

 

Okay so I don't have a distributor. What's that rectangular box with the 6 spark plug wires coming out of it called.


That's nice but what does that even mean? Are we talking minutes, hours, days, weeks, what? It's been days. I've had this code since before I even bought the thing. And I also don't think your interpretation of the code is comprehensive. Other possible causes are taht the OBD "self-test" (or whatever it's called) hasn't completed. Yet. It's been days and it hasn't completed. Yet. I don't think it's going to complete, because I think there's a problem with the computer. or whatever.

Right but then what do I do about it.

I'm in process of figuring out a way to actually test the oil pressure with a gauge. I discovered just yesteraday that the oil pump is about $100 and, unlike another vehicle I worked on years ago, it's "externally mounted" and so I won't have to do a total engine tear-down to replace the oil pump. I'm tempted to replace the thing simple because the truck has 190K miles on it. I'll know more when I get the oil pressure reading.

Vacuum leak where? How to find it? If there was a vacuum leak, don't you think there'd be some kind of code somewhere? Could the vacuum leak have to do with either the ABS or the Air-Bag System?

 

That is the ignition coil.

For the vacuum leak you will need to either do a smoke test or visually inspect all the vacuum hoses and relevant gaskets.

The P1000 is set every time the codes are cleared. The PCM relearn starts over and there is a certain # of miles that must be driven plus a certain # of drive cycles, engine on/off and hot/cold cycles, speed fast/slow, etc. It may take several days under normal driving conditions to reset. This code is generally ignored, it is a tell-tale for an emissions inspector that the system has been reset and not all the tests have been completed so that the emissions test will not be a true representative example of the emissions that the vehicle... emits.

You bought a used vehicle, which always means "you bought someone else's problems that they didn't want to fix". So you should expect to need to do some deep troubleshooting knowing that it had the check engine light on before you bought it.

 

Ah Ty, you need to start all over with this truck.
It's nothing like you had before. Forget past experience, it does not apply.
You are displaying indications that you don't know by what you are saying.
There is no distributor because the ignition is all in computer fire order control when the coils fires the plugs as well as the 6 fuel injectors in the same order.
This 'engine' is fully controlled by a computer. That's where the codes are coming from.
In this system design the computer is fed some troubles from other systems unrelated for convenience of trouble alert..
The ABS is one because the computer does not control it in any way.
Oil pressure is mainly an outside function to the Dash and only gets the computer involved on a secondary basis if the coolant temperature should go far enough out of limits or the wire harness is in fault.
The P1000 you have correct, however to see which diagnostics are not complete takes a Scanner to see.
If any of those tests fail, a code for that system will be set.
Very often the fuel system test takes a log time to complete especially on an older truck.
Rough running can be a number of causes from plug wires to 'over richness'.
You see how much different this is from your last vehicle?
Go about this from a new start and keep the issues separate because you don't know the vehicle just purchasing it.
This is the help you need 'first' before you can solve all the issues or make decisions.
It's a new ball game.
Good luck..

 

Do ignition coils go bad? This thing runs like it's not getting fire sometimes. New plugs & new wires. What else is there to think about besides this?


The check engine light is now off.

 

Yes.








......

 

So how do I test the ignition coil to see if it's bad or not. Would a bad ignition coil give a OBD code?

 

There are over 2000 codes associated with the computer system.
Faulty coil drivers or coil primary set P035X codes.
P030X are set for cylinder misfire codes.
If you don't have either, there is no issue with ignition.
The computer does all the testing. All you need is the codes to ID what the issue is and which one.
Good luck.

 

The P1000 code means the computer hasn't completed testing. I've owned the truck over a week. It hasn't completed in a week. What if it NEVER completes. The fact that it won't complete supports my theory that the computer itself is the problem. Plus all the extraneous codes that may or may not have something to do with the computer. I have two codes, two indicator lights on the dash and engine that runs rough and the only "next step" advice I have is to search for a vacuum leak.

But the computer never completes the testing.

 

Each self test monitor (I think there is a maximum of 11 monitors for your year) has a set of conditions that must be met before the monitor will execute its self tests. An example would be that the EVAP monitor requires, among other things, that the fuel level in the fuel tank be between 25% and 75% of capacity in order for it to execute. When the monitor runs, if the self test finds an issue it will cause a DTC to be stored. (Some DTCs cause the SES lamp to turn on immediately while other codes will only turn the SES lamp on if they occur during two back to back trips.) After all monitors have executed the P1000 code will be cleared.

Most scan tools will display which monitors have run successfully and which one(s) have not.

 

If you really want to figure out what is going on get a diagnostic tool that can read live data and show the individual emissions test results such as Torque or an expensive scanner.
You sure are hung up on that P1000.
How many miles have you driven it?
It may take several weeks for all the tests to complete under normal conditions.
The rest of this post is straight from regarding how to complete the drive cycle. If ALL these conditions aren't met, the P1000 will persist. Notice that 1/2 to 3/4 tank of gasoline is required.

Ford Motor Company Driving Cycle

Description of OBDII Drive Cycle
The following procedure is designed to execute and complete the OBDII monitors and to clear the Ford P1000, I/M readiness code. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the "OBDII Monitor Exercised" column. When the ambient air temperature is outside 4.4 to 37.8°C (40 to 100° F), or the altitude is above 2438 meters (8000 feet), the EVAP monitor will not run. If the P1000 code must be cleared in these conditions, the PCM must detect them once (twice on some applications) before the EVAP monitor can be "bypassed" and the P1000 cleared. The Evap "bypassing" procedure is described in the following drive cycle.
The OBDII Drive Cycle will be performed using a scan tool. Consult the instruction manual for each described function. NOTE: A detailed description of a Powertrain Control Module (PCM) Reset is found in this section, refer to the table of contents.
Drive Cycle Recommendations:

• Most OBDII monitors will complete more readily using a "steady foot" driving style during cruise or acceleration modes. Operating the throttle in a "smooth" fashion will minimize the time required for monitor completion.
• Fuel tank level should be between 1/2 and 3/4 fill with 3/4 fill being the most desirable.
• The Evaporative Monitor can only operate during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize "fuel slosh".

WARNING
STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN PROCEEDING THROUGH THE FOLLOWING DRIVE CYCLES.
For best results, follow each of the following steps as accurately as possible:
OBDII Monitor
Exercised Drive Cycle Procedure
Purpose of
Drive Cycle Procedure Drive Cycle
Preparation 1. Install scan tool. Turn key on with the engine off. Cycle key off, then on. Select appropriate Vehicle & Engine qualifier. Clear all DTC's/ Perform a PCM Reset. Bypasses engine soak timer. Resets OBDII Monitor status.

2. Begin to monitor the following PIDs: ECT, EVAPDC, FLI (if available) and TP MODE.
Start vehicle WITHOUT returning to Key Off.

3. Idle vehicle for 15 seconds. Drive at 64 Km/h (40 MPH) until ECT is at least 76.7°C (170° F).
Prep for Monitor Entry

4. Is IAT within 4.4 to 37.8°C (40 to 100° F)? If Not, complete the following steps but, note that step 14 will be required to "bypass " the Evap monitor and clear the P1000. Engine warm-up and provide IAT input to the PCM. HEGO

5. Cruise at 64 Km/h (40 MPH) for up to 4 minutes. Executes the HEGO monitor. EVAP

6. Cruise at 72 to 104 Km/h (45 to 65 MPH) for 10 minutes (avoid sharp turns and hills) Note, to initiate the monitor: TP MODE should =PT, EVAPDC must be >75%, and FLI must be between 15 and 85% Executes the EVAP Monitor (If IAT is within 4.4 to 37.8° (40 to 100°F)) Catalyst

7. Drive in stop and go traffic conditions. Include five different constant cruise speeds, ranging from 40 to 72 Km/h (25 to 45 MPH) over a 10 minute period. Executes the Catalyst Monitor. EGR

8. From a stop, accelerate to 72 Km/h (45 MPH) at 1/2 to 3/4 throttle. Repeat 3 times. Executes the EGR Monitor. SEC AIR/CCM (Engine)

9. Bring the vehicle to a stop. Idle with transmission in drive (neutral for M/T) for 2 minutes. Executes the ISC portion of the CCM. CCM (Trans)

10. For M/T, accelerate from 0 to 80 Km/h (o to 50 MPH), continue to step 11. For A/T, from a stop and in overdrive, moderately accelerate to 80 Km/h (50 MPH) and cruise for at least 15 seconds. Stop vehicle and repeat without overdrive to 64 Km/h (40 MPH) cruising for at least 30 seconds. While at 64 Km/h (40 MPH) , activate overdrive and accelerate to 80 Km/h (50 MPH) and cruise for at least 15 seconds. Stop for at least 20 seconds and repeat step 10 five times. Executes the transmission portion of the CCM. Misfire & Fuel Monitors

11. From a stop, accelerate to 104 Km/h (65 MPH). Decelerate at closed throttle until 64 Km/h (40 MPH) (no brakes). Repeat this 3 times. Allows learning for the misfire monitor. Readiness Check

12. Access the ON-Board System Readiness (OBDII monitor status) function on the scan tool. Determine whether all non-continuous monitors have completed. If not, go to step 13. Determines if any monitor has not completed. Pending Code Check and Evap Monitor "Bypass" Check

13. With the scan tool, check for pending codes. Conduct normal repair procedures for any pending code concern. Otherwise, rerun any incomplete monitor.
Note: if the EVAP monitor is not complete AND IAT was out of the 4.4 to 37.8° C (40 to 100° F) temperature range in step #4, or the altitude is over 2438 m. (8000 ft.), the Evap "bypass" procedure must be followed.
Proceed to step 14. Determines if a pending code is preventing the clearing of P1000. Evap Monitor "Bypass"

14. Park vehicle for a minimum of 8 hours. Repeat steps 2 through 12. DO NOT REPEAT STEP 1. Allow the "bypass" counter to increment to two.

Reprinted on OBDII web site courtesy of Ford Motor Company

 

That could be the problem. I've deliberately not filled the tank up all the way in case I have a fuel pump problem or similar. I'll fill the thing with gas and see what happens.

 

About 50 miles.

What else do I have to go on? I have a rough running engine and the only suggestion is a "smoke test", which I've just researched yesterday and today and I'll be performing, but still. I think it's pretty obvious that if you have a problem and the only relevant code is P1000, then P1000 is what you look at.

I bought this truck last week for $2,000. I see the extended cab F150's being sole for more than twice that. The Seller acting very twitchy, like he couldn't get rid of it fast enough, like he knew there was something majorly wrong with it and was trying to hurry-up the sale so I wouldn't have time to find it. So, thinking this deal was too-good-to-be-true, I'm looking for the problem. No evidence of a cracked head or blown head gasket. Oil pump is on the list of possibles. The only serious symptom I find is the engine runs rough, and the only hint I get is this P1000 code and so that's what I look at. I didn't even know what a "smoke test" was until just last night. Maybe that will fix it. IDK. I fix computers for a living, so when the computer says "P1000", then P1000 is what you pay close attention to. One theory is that the Seller "did something" to prevent the diagnostic from completing in order to hide (whatever). Like I said, the deal looked really good, and the Seller looked shiesty as f---. So yeah, I'm a bit paranoid. Waiting for the other shoe to drop.

Is it possible to disable the computer that gives the diagnostic codes in order to hide serious problems?

 

Reading thru this post, I think I know exactly what your problem is Tyrone..

First of all, yes, the coil pack does go bad... But if yours was bad, it would be much more obvious. I had to replace my coil pack a few years ago. The check engine light was flashing and the pinging was real loud. No power either... New coils/wires/plugs fixed it right up.

You said it idles rough, but the light is off now. So I'll bet it's the little vacuum hoses under the intake manifold. My truck did the exact same thing. Same mileage too...

Both of those hoses are hard to see. They're tucked under the intake manifold on the passenger side...

For the rear one, you have to just reach in there and feel for it with your fingers. It's a little rubber elbow, and as soon as you touch it, you'll feel how the "L" part is worn thin.

The front one is a little easier to find, but it's still hidden pretty good. It's near the front of the manifold, on the passenger side again... I'll try to get you a picture.. Good luck!