Tough to start and poor low end performance

[jkichline]

Like the title says. What do you think?
It seems to start OK when cold. But if its a little warmed up, it takes a ton of cranks and some gas (sometimes floored) to get it going again.

Also, power from 1-4Krpms is terrible. Maybe butterflies are stuck open? I'm not sure.

Today, I brought some electronic cleaner to work. I'm going to take the MAF out and clean it during lunch. I cleaned it up a little bit about 1000 miles ago but that was before I knew how to clean it correctly. I used carb cleaner (VERY LIGHTLY) and dried quickly with compressed air. If I wrecked it, I have a spare MAF at home in the garage. Should I be able to read a voltage off the sensor at idle (or any RPM) and know if its working properly?

 

[projectSHO89]

I'd suspect:

Fuel pressure leakdown, possibly leaky injector(s).

Secondaries not closing when engine starts - easy to observe.

Just unplug the MAF sensor and see if the driveability issues go away. Ignore the CEL for this test. Yes, you can measure the DC voltage, don't have the values handy, though.

Steve

 

[Rockledge]

Next time it happens, pull the vacuum line off the fuel pressure regulator and check it for fuel. There shouldn't be any.

 

[NJSHO]

Dont floor the gas when you are trying to start the car. This tells the computer to crank the car but not fire. Take a look at your IAC.

 

[Rockledge]

Dont floor the gas when you are trying to start the car. This tells the computer to crank the car but not fire. Take a look at your IAC.

On fuel-injected Fords, flooring the gas pedal causes the PCM to shut off the fuel injectors while it keeps the throttle plate wide open. So in essence, it works as a "reverse choke". The engine can still fire up, though.

 

[jkichline]

Thanks for the info guys. I cleaned the MAF during lunch and took it for a ride. Its definitely better than it was. After it warmed up, I stalled it (on purpose) and it fired back up with no problem and no gas pedal applied. Before I cleaned it and it stalled, it would be most difficult to start. It was only a 3 mile test drive and the car warmed up. I think the issue is gone but the real test will be on the way home tonight.

What should I be paying attention to when I look at the IAC?

I didn't observe the secondaries when I started (I forgot) but I will on the way out of here.

I don't think I have a leaky injector. I've had that before in my T/A and that made the car act differently than this. The leaky injector caused random misfires that you can easily feel when you're getting on it. I didn't do any fuel pressure measurements. I didn't look into it further because of my gut feeling was that it wasn't the problem.

 

[Snake2715]

Have you reset the idle lately? Lost power to the car by changing a battery etc? Maybe thats your problem?

 

[tjburns]

I have this exact same problem, only the guys at the shop said they suspected the timing belt, and/or plugged cats. We cleaned my MAF today and the same thing is still happening....ive got a 95 ATX....starts fine when cold...but even minnutes after first stop it wont restart. bogs real bad under heavy acceleration, backfires when you try to start it....im really at a loss here and would rather not just start replacing random parts....which is what ive been to. Im about to change the timing belt unless anyone has a better idea.

 

[jkichline]

How do you reset the idle?
After cleaning my MAF which didn't look dirty at all to me.... but I cleaned it anyway.... its running MUCH better. I think my problem is completely gone. Only time will tell. My low end is back and starting is much easier. My secondaries are closed at startup and are opening right at 4K. It feels like a new car right now. Now that I said that, I better call a tow truck now...

tjburns,
Have you done your upper 60K recently? Check you plug wells. I had similar symptoms and my plug wells were completely filled with oil. I did my upper 60K (even though all it really needed were new plug well seals). It sounds like you are missing. I'd be looking at ignition problems first.
I don't think your timing belt could be causing this unless it was off a couple teeth or slipping. If you have an EGR valve, make sure that is working properly. I always suspect the cat LAST because its expensive as crap and the biggest PITA to replace.

 

[tjburns]

Replaced intake manifold gaskets, valve cover gaskets and plug well seals, as well as plugs and wires, egr valve....ive blown throuhg 3 starters since i purchased the car a little over a month ago. plug wells are dry. we thought ignition, but werent sure where to start after the plugs and wires. any help would be great as im at my wits end and need to make this a daily driver in a couple weeks.

 

[jbeano]

Bad 02 sensors can cause bad idling, stalling and hard restart.They aren't off by enough to light the cel but still enough to cause your symptoms.

 

[jkichline]

Ah yes. The O2's can screw you. I actually bought 2 for mine when I did my upper 60K and I didn't put them in yet. I don't think I'm having trouble with that right now, but I might put them in in the morning. I just drove the car over 200 miles today. Ever since I cleaned the MAF sensor, it seems to be good. It seemed a little sluggish tonight but I think it was because I had the A/C on.

 

[Rockledge]

Replaced intake manifold gaskets, valve cover gaskets and plug well seals, as well as plugs and wires, egr valve....ive blown throuhg 3 starters since i purchased the car a little over a month ago. plug wells are dry. we thought ignition, but werent sure where to start after the plugs and wires. any help would be great as im at my wits end and need to make this a daily driver in a couple weeks.

Have you tried pulling codes? You don't even need a code reader, you can use a paper clip:

http://www.shophoenixproject.com/eec/eec.htm

 

[jkichline]

Replaced intake manifold gaskets, valve cover gaskets and plug well seals, as well as plugs and wires, egr valve....ive blown throuhg 3 starters since i purchased the car a little over a month ago. plug wells are dry. we thought ignition, but werent sure where to start after the plugs and wires. any help would be great as im at my wits end and need to make this a daily driver in a couple weeks.

Ditto on reading codes.... Do you have a check engine light on?
3 starters in a month????? are they new starters? Or, are you blowing them from cranking the engine too long?

Do you know if your fuel pressure is good?
Does it run fine after a cold start?

I've heard of these symtoms when the PCM goes bad. The chip becomes worthless when warm.

First step, check codes. Hopefully that helps.