I got a quick (and hopefully simple) question. I have a 1995 F150 with a remanufactured 5.0 that's completely stock (unless you count shortys and a K&N) with less then 10,000 miles and 2 oil change so far. (I bought the truck with 3,000+ miles and I'm unsure how much the previous owner changed the oil during the break-in period)

In the winter (60 degrees Farenheight or colder) my truck starts up immaculately every morning, doesn't take more than 2 seconds to turn over and exhaust is clean with a smooth idle.

Now for the question. Last summer whenever it got over 75 degrees outside it consistently sputtered for about 3-4 seconds on startup then idled out fine (sometimes died and required a few turnovers when over 90), oil pressure was normal, my exhaust was stock with cats and the exhaust looked clean.
This summer it has a true duel with Flowmaster 40s, no cat or resonator, and upon startup with the same temperatures outside mentioned above or higher, it sputters like last year but now with a little blue smoke visible in the exhaust for a few seconds. It's not after every startup, only after sitting for more than 2 hours. It doesn't appear when idling or driving. The odd part is that I don't smell burning oil, just incredibly rich gas fumes while it stutters. The oil pressure also fluctuates to the lower side way more than usual. I check oil levels weekly to make sure it's never too low or too high (I've been fighting a leak on the oil pan gasket), but a few weeks ago I put some StopLeak in and the problem seems resolved.

So, am I stressing over normal symptoms of an older truck during excessive heat? Or is this something I should genuinely look into further?

Thanks.

 

Check for engine codes. You can count the flashes on the check engine light, if you don't have a code reader.
https://www.lincolnsonline.com/tech/00239.html
Also check the fuel pressure. My '88 would start fine cold, or on quick restarts, but if it sat for a half hour or more, on a warm restart, it would take two tries. It was a failing fuel pump.There's a thread on this forum for checking engine codes. (EDIT: Thread on checking fuel pressure is posted below)

 

https://www.ford-trucks.com/forums/1...rd-trucks.html

 

I have a code reader and have no codes showing up other then (111 - Clear) And I checked my fuel pressure about 3 months ago (was fixing some other issues that were injection related) and it's been fine since. What is really getting to me is the small spout of blue exhaust upon startup when 80+ outside, but never when its below 75. I've started it three times tonight when it's cooler with plenty time in between and it hasn't blown blue. But it was earlier today at work when it was 86 outside

 

I suspect ECU capacitors leaking.

 

is there anyone on these forums who does repair on these older ECU'?

 

I personally examined the ECM a couple months ago and it didn’t show any signs of blown/leaky capacitors (I was trying to solve a different issue) so is this a phenomenon that would only occur during high temperatures outside? I started my truck up this morning after it sat all night and there was no blue smoke or engine stutter (It was colder then 65 outside). Maybe the ICM is overheating?