I’m a new guy to the board and I don’t own a truck (but would like to).

Yes I know I'm asking for all sorts of car flack from a truck board but I have a weird problem with my '95 Crown Vic. My mechanic spent two days trying to figure it out and finally he gave up and with a lot of misgivings said, "Take it to Ford". Problem is I'm afraid to go near a dealership, as I know they will probably start changing expensive parts until they hit the right one.

My engine is a SOHC 16 Valve 4.6L V8, sequential multi-port electronic fuel injection (SEFI), on board diagnosis Level II (OBDII) with Ford electronic engine control V, distributor less system (DIS) ignition system with 2 modules and 8 coil packs.

My problem started out as a starting issue. In the morning I'd hit the key and it would start then promptly stall. On a second start it started properly and ran fine. This got gradually worse as the cold weather hit. Finally last week, at -25, it would start but I had to sit in it feeding gas until the car reached about 3/4 operating temp before it would idle without stalling. Then I noticed a new problem, while driving the engine would surge. It would lose power for a few seconds and then return to normal.

So my mechanic started by replacing the IAC (idle air control). This helped the start but didn't affect the surge. He figured the surge had to be either a vacuum leak or a fuel problem. He bypassed all the accessory vacuum lines and checked everything he could think of, no leaks. He checked the fuel pressure; it was good 32 psi at start and 75 psi at max bypass. So next he swapped the MAF (mass airflow sensor) with no improvement. He now thinks it must be a problem with the ignition. The engine isn’t reporting any codes, but he said this isn’t surprising since I guess the early ECC-V systems first used in ’95 don’t report ignition codes correctly all the time. The surging is so bad now that the car is a little scary to drive. When stopped at a light with foot on the brake, the car will all of a sudden increase idle RPM and the car tries to take off. To drive it now I shift to neutral at all the lights and in stop and go traffic I have to stay about 15’ back from the guy in front so that the silly car doesn’t climb his back bumper.

Anyone have any ideas. I’m terrified of having to turn a dealership loose on this. I figure they’ll start by replacing the ECC and anything else that connects to it.

Help anyone!!

Bill Mounteer
Calgary, Alberta

 

Sounds very similar to a situation that my mother had on a 1997 Merc Sable. The problem was that the dealer could never duplicate the symptoms that you mentioned which made the cause impossible to diagnose. After about a year and a half, and six tries with the dealer, it was finely determined that the transponder (part of the ignition-key anti-theft system) had gone bad. Cost $175 to fix, no problems since...Good luck.

Greg

 

Greg,

Thanks for the reply. My '95 doesn't have any anti-theft stuff, after all, who would steal a Crown Vic. My insurance agent told me that theft coverage for my car was a formality

Maybe a better description of my surge problem. When driving at a fixed speed, the car will periodically feel like it has hit a big puddle, the speed drops and it slows down enough, fast enough that you need to hang on. Then it "clears itself" and away you go. At a red light, the idle is so low it feels ready to stall, then it will decide to race a bit, then return back to a low idle. If I had a carb I'd be cleaning the jets.

Bill Mounteer
Calgary, Alberta

 

sounds like your coil pack(one of them at least) is going bad

 

TexfordD, thanks for your reply.

If it were one or more coil packs wouldn't it be more like a misfire situation with rough engine and maybe backfires.

The most graphic example I can think of to illustrate what the car does, while driving at constant speed, every half block or so you slow right down as if you hit a patch of real thick air. The power only drops for a second or two. Could a bad throttle position sensor do that?

It's a real head scratcher.

Bill Mounteer
Calgary, Alberta

 

Just a thought did you change the gas filter
just because you have pressure dosent mean
you have voulme

 

I've run into similar problems on CV's and Town cars, they have the same engines, the problem is that the egr passages get plugged up with carbon over time and on high mileage cars. Your car should have the aluminum intake manifold with the intake elbow that goes into the manifold at the back of the engine. The intake manifold needs to be removed and taken apart and cleaned out. This has worked for me about a dozen times out of a dozen tries. Also the fuel filter is a good place to start as it is easy and cheap. Good luck.

 

For some reason, EGR keeps coming to mind for me too... Just a thought :-)

 

Status, we've gone over all the vacuum lines twice and found no leaks. We cleaned the sponge filter in the EGR gizmo using info I came across at http://www.v6power.net/ubb/ultimateb...&f=20&t=017025 This is a really good tip as niether I nor my mechanic even knew this thing came apart.

svt_sc_f150, will the car report any codes if the EGR ports are plugged?

Mine isn't giving codes, my mechanc says early ECC V systems didn't report all codes properly until they got to the '96 and '97 versions. (sounds like Micrsoft).

Thanks again guys for all the help, this is a great board.

Bill Mounteer
Calgary, Alberta

 

Pull the upper intake and I'll bet you'll find the egr passage is clogged with carbon it only takes a little time and you can usually reuse the gasket. There a few small ports in the intake manifold that quite often clog, thats the place I would start. Old fossils like yours don't always set codes. If you want to make the job real easy pull the wiper assy off it only takes a few minutes and will give you all kinds of room.

 

I want to second the idea of the egr. The position sensor would only set a code if the valve itself was stuck, if the passages were clogged it would not set a code. The fact that your IAC was probably plugged up( you said you had it replaced) is a good indication that you might have some build up. Might also look at the throttle position sensor. sometimes they get a bad spot that causes the computer to think the position is closed even when you are trying to accelerate. Let us know!!

 

Sometimes it will, sometimes it won't, depends how bad it's plugged up. If the egr can flow a little bit, it probably won't.

 

I agree with the EGR.
My ex had a chevy that did the exact same thing. She'd be driving and it would feel like a huge head-wind would slow us down. Plus sometimes it would take up to 30 seconds of cranking before it would start.
Until she got the EGR valve replaced and the passages cleaned, the mech told her to rev the engine (mind you this was a 19 year old working at chevy cause his daddy was a sales manager ) to clear the passages. Seemed to work a little, but once she got the EGR replaced it was like a whole new engine.
Either way good luck.

 

More symptoms.

When I start the car in the AM, it starts right away. If I don't play with gas, it stalls - no it more dies as if chopped off. What I'm trying to say is it doesn't sputter or load up, it just stops. So start again and play with the gas to keep it going. Every time it is restarted I get a cloud of greyish smoke out the tail pipes. The car doesn't burn any oil and the rad isn't losing fluid so I assume it's clearing out a lot of excess fuel from the cylinders. This process continues until the temp is at 3/4 normal. At that point it will idle, sort of. The idle speed is quite low, barely ticking over. About every 15 to 30 seconds it seems to clear up and the idle surges up to what would normally be the idle speed for a cold engine - even though at this point it's almost up to normal operating temp. It can be driven, but at any light or stop in traffic I have to put it in neutral and keep feeding gas. While driving between lights the engine speed continues to fluctuate every 15 to 30 seconds. When it surges, the car feels more normal. When it's between surges, the car feels heavy and unresponsive. From that I'd say what ever is causing the problem is running abnormally most of the time with little bursts of proper operation. The surge at a light when it's in gear is probably the result of the higher idle speed when it surges. I filled the car with gas last week (gas is good and from a very high volume station) and have "used" about 1/4 tank to go about 20 miles. As such it must pumping a lot of gas somewhere.

More back ground. About a year ago the car developed a starting problem. My normal starting procedure is to hit the key without touching the gas. Well about a year ago every morning I'd hit the key and it would start - then quit. Hit the key a second time and it started normally. Any subsequent starts later in the day were normal. This gradually got worse. I assumed it was the IAC and since it wasn't that big a deal I let it slide. When the temps dropped to -30 it became a problem and was the start of this current quest. The surging problem started after the -30 weather. So could a long term IAC cause the EGR to foul?? If so I guess the EGR passages are going to get cleaned next. If that's the problem, I guess I need a whack in the head for letting the IAC problem get out of hand.

Sure would make life easier if the silly computer would kick out some usable codes.

Thanks again for all the really good input, great board!!

Bill Mounteer
Calgary, Alberta

 

Ok, the greyish smoke and the high fuel usage tells me you probably have 1 or more injectors that are sticking, and that the cat converters are probably plugged from being flooded with raw fuel. Remove the spark plugs and check them for fuel fouling.