Engine light flashing

[Harriet Graham]

Check engine light is flashing and it not changing gears good.When I pump the gas or give it a second to change gears it picks up. I was in a traffic accident about a month ago and smashed into the medium. I took it to a mechanic and at first it would not read, almost like there was no computer. He looked around and found a short. Got that fixed and cleared the computer. He said that the computer said It had been on for over a year. It had not. Today he told me it seems the computer is sending wrong messages to the transmission. Any help please.

 

[Steve McKellop]

A flashing check engine light indicates a condition in which engine malfunction is subject to cause damage to the cats, ie. severe miss, severely over rich condition. Transmission warnings are indicated by the OD light flashing. Better have your mechanic do some more looking underneath the vehicle ! ! If insurance is paying I'd suggest taking it to a GOOD Ford dealership service dept.

 

[Tom Schindler]

I have heard of the OD light flashing, but never the Check Engine light flashing.





Tom

 

[Steve McKellop]

I have heard of the OD light flashing, but never the Check Engine light flashing.

That's a good thing.......



From the 2004 Sport Trac PC/ED Manual

Generic Misfire Processing

The acceleration that a piston undergoes during a normal firing event is directly related to the amount of torque that cylinder produces. The calculated piston/cylinder acceleration value(s) are compared to a misfire threshold that is continuously adjusted based on inferred engine torque. Deviant accelerations exceeding the threshold are conditionally labeled as misfires. The calculated deviant acceleration value(s) are also evaluated for noise. Normally, misfire results in a nonsymmetrical loss of cylinder acceleration. Mechanical noise, such as rough roads or high rpm/light load conditions, will produce symmetrical acceleration variations. Cylinder events that indicate excessive deviant accelerations of this type are considered noise. Noise-free deviant acceleration exceeding a given threshold is labeled a misfire. The number of misfires are counted over a continuous 200 revolution and 1000 revolution period. (The revolution counters are not reset if the misfire monitor is temporarily disabled such as for negative torque mode, etc.) At the end of the evaluation period, the total misfire rate and the misfire rate for each individual cylinder is computed. The misfire rate evaluated every 200 revolution period (Type A) and compared to a threshold value obtained from an engine speed/load table. This misfire threshold is designed to prevent damage to the catalyst due to sustained excessive temperature (1600F for Pt/Pd/Rh conventional washcoat, 1650F for Pt/Pd/Rh advanced washcoat and 1800F for Pd-only high tech washcoat). If the misfire threshold is exceeded and the catalyst temperature model calculates a catalyst mid-bed temperature that exceeds the catalyst damage threshold, the MIL blinks at a 1 Hz rate while the misfire is present. If the threshold is again exceeded on a subsequent driving cycle, the MIL is illuminated. If a single cylinder is indicated to be consistently misfiring in excess of the catalyst damage criteria, the fuel injector to that cylinder may be shut off for a period of time to prevent catalyst damage. Up to two cylinders may be disabled at the same time. This fuel shut-off feature is used on many 8-cylinder engine and some 6-cylinder engines. It is never used on a 4-cylinder engine. Next, the misfire rate is evaluated every 1000 rev period and compared to a single (Type B) threshold value to indicate an emission-threshold malfunction, which can be either a single 1000 rev exceedence from startup or four subsequent 1000 rev exceedences on a drive cycle after start-up. Many 2004 MY vehicles will set a P0316 DTC if the Type B malfunction threshold is exceeded during the first 1,000 revs after engine startup. This DTC is stored in addition to the normal P03xx DTC that indicates the misfiring cylinder(s).



I, unfortunately have on other vehicles.:cry:

 

[zaffo oxnard]

Hey, mine just had the flashing CEL. Try plugs and wires first. I had a P0304 which was misfire on 4. Dealer found #4 gapped too tight, too small gap, incomplete combustion. Regapped theplug and all is well. hope yours is this simple.

 

[scott degroot]

In a nutshell a flashing check engine light means that you have a catalyst damaging misfire occuring right now and if you don't get it remedied that you will also be buying a catalytic converter if you let it go too long.

 

[scott degroot]

Tony,



Now I am throughly confused with the order of events with you situation. I was under the impression that the dealer told you the plug was gapped too tight, the plug then got regapped but you were still experiencing the same problem

 

[zaffo oxnard]

L1tech,

I replaced the original with iridiums 4 months ago. No issues.

2 weeks ago the CEL / bad idle started. Throwing P0304.

I replaced the iridium with autolite platinum gapped to .42 (i went and checked the tool i used in the garage - i used this to set the iridum and the replacement platinum) I know it is too tight, it is suppoded to be .52 - .56. I was too dumb to look at the sticker under the hood.

Also replaced the wires.

Then it went to the dealer who pulled #4 and regapped to solve idle.



I am thinking that I either had a hunk of carbon hit the #4 plug and narrow the gap (unlikely given my towing and heavy throttle over the hills at times), or that "winter gasoline" here in California caught up with me. More methanol. This sutff is supposed to have lower energy content, but I am not sure about harder to ignite? Maybe is just a slower burn? Combined with the smaller spark and it just was the total effect of a bunch of issues.



Don't know.



I will change the fuel filter. I use Costco gasoline 95% of the time, but I will do a distilled water decarbonize and throw a can of seafoam in the tank.



I changed the coolant and the ps fluid. I need to do another trans. fluid pan drain and adjust the tranny per the projects.



Love the old girl. I hope she keeps on keepin' on.



Thanks,

Tony

 

[Gavin Allan]

Go with stock plugs, properly gapped and torqued. Use anti-sieze on the threads and dielectric grease on the electrodes. Plub problems solved for a long long time.

 

[zaffo oxnard]

I am going to get the iridiums set properly and be a test case. The stock plugs were perfect for 80,000 and 9 years. We'll see if these do just as well. If I have any more issues, they are in the trash.



tony