rough starting

[RS6tofj80]

So i've baselined all fluids and am getting thru the suspension and fun stuff but I'm noticing that the truck starts rough.... it takes several cranks for it to catch, and seems to sputter just for the first few seconds then it runs great..... it doesn't seem to be warm /cold related...

Supposedly the PO went did the 90k service but i'm wondering perhaps if he skipped plugs or I might have coilpacks going etc or if there is a fueling issue..... it has a new Fuel filter and I can't imagine the pump would be bad... it is supercharged but exhibits no issues or codes/lights / pinging etc once it's running.

Battery is brand new AGM group 31

Thoughts ?

 

[duggy]

Did this start before your baselining or after?

Possible suspects:
Dirty throttle body
Dirty or malfunctioning cold idle valve
Fuel filter

 

[landylover21]

This happened to me after cleaning my throttle body. I realized I forgot to plug the MAF sensor back in. Although if you don't have any codes then it probably isn't this, but worth a quick peek.

 

[Odyseuss]

Never hurts to check the throttle body and clean it. If it's dirty, it can cause problems and it's easy to get to and clean. They definitely can get dirty and build up deposits around the throttle plate.

 

[CurbsEnthusiasm]

Mass Airflow Sensor and Throttle body cleaning could possibly help. At times the MAS cleaning is not enough and you have to replace it.

 

[ton504]

Any smoke out back when starting? Could be leaking fuel injectors. Fuel pressure bleeding down. Low compression. Basically alot of things lol.

Give us more info. Only on cold starts? How about a video?

And I believe spark plugs at 120k not at 90k. Factory recomended interval.

 

[RS6tofj80]

thanks all - the start is I suspect is due to old plugs... pulled one today and am ordering up a set and a batch of misc PM stuff....

Going to do filters, get a few backup coilpacks and do all the belts and hoses as they might of been skipped when they did the TB /Wp and a few other things at 85k it looks like...