No experience with the car. But judging from other cars, you should check fuel pressure when it’s having the problem. I would suspect fuel pump and filter. Sounds like a running lean condition when hot, which points to the pump, but could be as simple as a clogged filter. At over 5 years and 50k miles, I would start with the filter, especially if I bought it used. Also, if plugs have not been changed, it’s time.

maw

OP describes a misfire... Perhaps consistent with a failing ignition coil. I've not got to fiddle with one of these and am thus not aware of pattern failures... I'd be surprised if this vintage of them never has coil issues. The ECU pulls fuel from a cylinder it knows to be misfiring and will not try again until the key is cycled off and back on. All about protecting exhaust kittahs.

Lack of fuel will recover as soon as he is out of the throttle and leave codes for multiple random misfire or some such.

OP pull codes from the ECU. The flashing check engine light says that the ECU is aware of the problem and will have a treasure trove of useful data for diagnosis. Expect it to say which cylinder is misfiring.

If one cylinder is misfiring.... Swap ignition coils from the hole having a problem with a cylinder not having an issue. If the problem moves you know what to replace. Good opportunity to pull spark plugs to have a look and replace with fresh.

Bill, your “rough running” was my “running lean”. You can change the sensor if you want. But if the CEL went off and that’s a stored code, my sense is your sensor is still good. I would first change the plugs. While I’m at it, because it’s cheap and non obtrusive, I would change the fuel filter. Then I’d wait and see if the condition occurs again. If so, then I’d move to the sensors and fuel pump. But for now, it seems the sensors are functioning properly. Plugs are plugs, no mystery there. But what you describe is a failing fuel pump. They’ll sporadically run lean before failing altogether. If the condition returns after plugs and fuel filter (good to do no matter what), then I’d next suspect the fuel pump.

On my S55, he failing fuel pump was even more subtle. There would be periodic extended cranks before she would turn over. Every now and again, nothing constant or repeatable. I threw a crankshaft position sensor at it — no dice, same thing, still every now and again. This went on for years, but nothing to bother about. Then, I was driving the car, I hit the gas for acceleration and it sputtered and muttered, but kept running. Light fuel pressure was fine, and the car would cruise, but as soon as I put my foot into it, sputter and mutter. Lean condition, fuel pump. Changed it and filter, no problems since. So I’m just ruling out the things that it makes sense to do on yours, to isolate the fuel pump. New plugs and fuel filter never hurt, so I’m not advising against that. But from the beginning I suspect the fuel pump, based upon my experience.

GL and pleas keep us posted.

Cheers,

maw

To an O2 sensor.... A misfire is 'lean.'

OP a flashing check engine light only happens for a severe misfire. The ECU should be eager to tell a proper scanner which hole is/was dead. It will remember this for a long time. Start there.

JL, might you get a severe misfire and lean condition with no specified cylinder? And wouldn’t that almost certainly mean a fuel pump? The thought being a MAF or bad sensor can throw a CEL but not a blinking CEL...

maw

Maw a flashing check engine light will happen where there are multiple cylinders that are dead dead deadski long enough for the ECU to pick them out.... However; OP describes one dead hole. This is the easier scenario for the ECU to pick which hole it is.

Random multiple misfire can easily be an issue with just about any and all.

Certainly before condemning a fuel pump I'd have OP hook up a gauge and drive it with that gauge clearly visible such that we can see 'while making multiple awful misfires fuel pressure is low.'

In my E-55 I got to deal with many issues of driving along... Load it up and it cuts the supercharger... Is misfiring... No check engine light. That was really annoying and got fixed with ultimately replacing all plugs, coils, wires + screwing around with coil connectors.

Does the TTbent eight use air mass meters or is it speed-density? E-55 and my 275 are speed density.

Agreed on the gage. The problem with these pumps is they go slowly over time, triggering faults that are difficult to run to ground. Mine took years of mild annoyance before it got bad enough that it was easy to replicate, trace and fix. Short of that, as you know, it becomes a series of guesses.

maw

Misfires in the E-55 were especially annoying. At first it did it..... Dead hole. No codes. Cycle key and it was fine for weeks to over a month. Predictably it got more consistent over time but was still unwilling to share it's secrets. Finally narrowed it down to a coil. Replace it... Month or so later another fails. Rinse repeat. Especially fun is when a new coil decides to make for yet another new/exciting drivability issue. Been there. Done that. Half of them never make a check engine light flash. It had to run really bad for that.

Intermittent issues are are the most annoying of all! Currently the S-65 shuts Command off intermittently. Grrrr

Right. Mine never threw a code. And when it started misfiring, it was at a time when it was time to change the plugs anyway, so that's what I thought. My indy was like, "Maybe. But I have a suspicion." Connected the fuel gage, told me to start the car ... extended crank and no fuel pressure. Pump and filter, have a nice day. Car was going into Winter storage, so I did the plugs the following Spring. Had I shut it off when it started misfiring, I probably would have been stranded. I'm glad I just eased it over to his shop instead.

The point is, these cars do NOT like to run lean. Basic air, fuel and spark. If you have air and spark, then fuel delivery is probably the issue. The 65 cars were an anomaly, with coil packs and modules going bad. On everything else, if you've taken care of plugs and don't have pressure leaks, it's more likely the pumps. I haven't heard of any ECU issues on these.

maw

P.S. Unfortunately, these pumps look like they are in the tank. Brilliant.