So my 06 5.3 with headers, Brian tooley stage 2 camed engine has some hot start issues. Cold start is great. Always immediate. But if I drive let's say to the store and go in and pick something up and it takes let's say 20 mins and try to start it it half way fires then cranks a few seconds then runs at a really low rpm maybe 100-200 for a second then comes up to normal or if I blip the throttle it come up fine. But if I shut it off and restart immediately it starts just fine. I tuned it my self with hp tuners. I'm trying to figure out if it sounds like an injector or a tune problem. I have adjusted a few things in the tune but none have helped. This was my first tune ever so I'm a little green you could say. I can post the tune if that would help. So what do y'all think? Sound like the tune or injector leaking if you were to guess?

 

Post the file and a log of a start. Make sure you're keyed on for about 20 seconds before cranking. Log the entire time, starting as soon as possible after key on and through the entire hot restart. Sounds easily fixable but will need the data.

Make sure you've got engine coolant temp and intake valve temperature in the log file.

 

A log file of an immediate restart would also be good as a comparison.

 

Thanks. I will get that done after work.

 

Have not been able to time it right to start hard. here is my tune. maybe someone can see the issues is there is any. Thanks.

 

ok got it to mess up starting. let it sit almost an hour then hooked up let scan for 20 seconds or so then cranked it. it started but was not super strong start. let it idle for a min then shut it off logged a few seconds then started it again. started great second time. what do yall think?

 

Well that didn't work out as planned. O2s took forever to come online lol. I'd have to say it looks lean on the restart though, judging from what is being commanded.

 

It does have headers on it. So maybe that's why the o2s took a while. The restart on the log started great. How would I adjust the lean start up?

 

Throw some cranking fuel and afterstart enrichment at it. More startup air probably wouldnt hurt either since you said blipping the throttle helps.

 

Give this a shot. The log commanded AFR numbers a fairly close match for the leanout factor coming from this surface, and seems to react once the value decrements out...probably a good start.