Contour Enthusiasts Group Archives Forums Modifications 3.0L Duratec fuel requirements for 3L SE

Geez, just stay out of the pedal for a few days till you burn the gas out. In the mean-time, put in a can of octane booster and take it easy. Mixing a half tank of 87 with a half tank of 91 is how they provide the 89 octane fuel anyway.
You probably have pinging from compression and low octane fuel and the computer is pulling timing. It could have been dirty fuel and if running the gas out and filling with premium doesn't fix it then check your fuel filter for clogging.

warmonger

Go buy a gallon of Xylene (117 octane) and pour it in.

That on top on the 87 in there will bump it to around 89-90 octane.

Even a couple bottles of the largest & best octane booster is not going to get you much more than one full point of octane.

It will probably still ping, but if you stay off the throttle it should not hurt the engine.

The PCM can only pull out so much timing though.

I'll get some tonight. Thanks for all the help. I guess I shouldn't let people use my car. Lesson learned.

Ok here is the good news.....I don't have to worry about getting on the gas too hard. The bad news....The dealer thinks I have/had a bent valve. The motor started knocking real bad when I pulled out of the parking lot. NO I was not smoking the tires. I was driving slow that day and it just went. The heads were redone back in September with the 3L. The dealer wouldn't do 3L valves or any custom porting so they reconditioned the old heads. Now I have possible top end problems that I hope doesn't affect the lower end. I've got less than 5000 miles on the new motor. Anyone know the redline for the 3L hybrid? I hit the old redline twice by not paying attention(down shifting).

Redline shouldn't be affected by the swap, but the clearance is an issue on the heads. If he decked too much off the heads, it's possible that one of the valves has been in contact with a piston. I'd be very suspect of that since he did the head work.

Rick

The head was only milled enough to smooth out any irregularities in the surface. It wasn't an attempt to increase compression even more. The original 2.5L valves were covered in carbon deposoits causing them to get stuck. The dealership had the heads sent out and "reconditioned". I tried to get 3L valves installed at that point but Ford said no. I know that hitting a valve with a piston is bad but if that is the case are pistons USAULLY destroyed by that if extreme caution is taken and the car is towed to the garage at the first sign of a problem? Not that it really matters I've been looking for a reason to get the 3L valves and a good P&P done. I just don't want to rebuild a 3L that only has 4500 miles on it.

Depends on how much contact there was with the pistons, but I'd say out of 4 cases when I worked at the dealership and once in my own case, not once did we have to replace pistons when the valves contacted them. Of the five, two of the cases had the valve broke off. In one case there was no valve damage and only small nicks in the pistons, and in the two cases with the broken valves, the head was damaged both times, but only required replacement on one.

I hope this isn't confusing to read, but suffice it to say that in all five cases the pistons were fine, but I'd be more worried about the heads and what caused it in the first place. It doesn't matter that it was ford who reconditioned the heads, if the clearance was reduced by a shop milling too much off the heads then it is still their fault. If it happened soon after the install, its possible that they were timed improperly, possible that the guides were worn or tensioner had a problem, or other small issues. Bottom line is you need to determine the exact cause of the failure.

Also, GET A SECOND INDEPENDENT OPINION!!! I can emphasize this enough as I have seen attempted fraud first hand while I worked at the dealership by mechanics who were trying to make work for themselves. This is the exact time of year to be carefull since Christmas has tapped out most people's savings and they tend to have less work done on cars. Therefore the mechanics are working flat rate and are not making money at this time of year...there is a tendency to 'find' things wrong and in some cases capitalize on simple easy jobs by making mountains out of molehills. The car sets in the shop for a week and the mechanic quickly fixes the problem the last day and gets paid for many more hours.
Yes its sad, I was always concientious and most mechanics are...just not all.
Then there is the occasional mis-diagnosis.
So get a second opinion.

warmonger