New plugs, now have hard start

[~0zzygirl~]

Hi, my husband has a 2002 Sport Trac. He changed out plugs and wires with regular Autolite plugs - not platinum. Runs much better, idle is much stronger and smoother, but now it has a hard start when cold. Warm starts are fine. Any ideas?

 

[BrooklynBay]

Welcome to this forum! Did he check the gap of the plugs before he installed them? Did he compare the resistance of the old cables to the new ones?

 

[~0zzygirl~]

Welcome to this forum! Did he check the gap of the plugs before he installed them? Did he compare the resistance of the old cables to the new ones?

Thanks for the welcome and the reply... I know he made certain they were gapped correctly. I'm not sure about the cables. Most likely, he just got what Autozone recommended.

Is there any known issue in these engines with using plugs that aren't platinum, especially in colder climates? He says the colder the morning, the harder the start. No problems on a cold start in the middle of the day when the temps are up. Makes me think the regular Autolite plugs aren't hot enough... do the platinum plugs make a hotter spark?

 

[BrooklynBay]

Did he replace the fuel filter? It might be a good idea the check the ECT sensor, and clean the MAF sensor.

 

[~0zzygirl~]

Did he replace the fuel filter? It might be a good idea the check the ECT sensor, and clean the MAF sensor.

He is planning on replacing the fuel filter, but it hasn't been done yet. I also thought about the MAF sensor, but the hard start wasn't there before the plugs were replaced. The old plugs were in terrible shape and the idle was weak, but it always started right up. I'm pretty sure they were the original plugs, 125k+ miles and they were worn down to a nub.

Is there a reset that should be done after something like that? I know on my car, you would do a reset and the PCM "re-learns" the new fuel trims, etc.

 

[BrooklynBay]

Every model is capable of learning a new pattern after it's reset.

 

[~0zzygirl~]

Every model is capable of learning a new pattern after it's reset.

Maybe a reset would help, then. How would you do a reset on this truck?

 

[BrooklynBay]

Either with a scanner or by disconnecting the battery for a few minutes.

 

[bdmaash]

thought autolite iridium plugs were stock on the truck.
- a step above platinums even.