This morning I started her up, and went into the garage while she warmed up. I hopped back into the car and was greeted by the SES light. After a quick scan I got code P1415, which from what I've read is a secondary air related code, probably just a lose hose. I didn't have time to check the hoses today, but while I was driving I got another fault about 25 miles later, Cyl 8 misfire. The car isn't missing, as far as I can tell, but I've herd that a vacuum leak can cause engine stutter that could lead to a misfire code? Can someone confirm this? It's idleing much rougher since the SES light, mostly when its cold.

 

Yes check the vacuum lines on your SAI one is loose or cracked.

 

I just checked and tightened all the SAI related hoses, and found one without a hose clamp, I zip tied it temporarly. The black round vacuum cannister on the left was also very lose, I tightened its bolts down and checked every little connection on the SAI system. Car seems to be fine now, no codes, knock on wood!

 

How many miles on your engine and has it been tuned along with new wires?
Second, never start your truck and just let it set, warming up, you will carbon up your engine, contaminate the oil and foul out your plugs.
If you have a 308 fault code, you do have a misfire and it does need to be delt with.

 

Ok heres the lowdown:

I checked all the SAI hoses, and everything is tight. When the truck is cold, it is very rough all of the sudden, it wasnt like this 2 days ago. I first got the P1415 code, cleared it, and it hasn't been back. Later that day I got the P308 code, cleared it thinking It had something to do with the vacuum leak as I just put in new NGK plugs and wires. That code hasn't been back and I've put on 50+ miles since then. I'm at a loss, the car was fine a few days ago.

Theres 100k miles on the engine. I thought the car was fine, but the roughness lessens considerably once the engine is warm.

 

Hey, it's a Rover and always full of surprises.
Wait and see what shows over the next few days.

 

The SES light hasn't come back on, but the truck is still idling rough especially when cold. It wasn't like this 2 days ago, just happened one morning so something failed. I've checked the hoses and cables, changed gas, done plugs and wires, cleaned the induction and seafoamed. I'm at a loss.

 

You smell any coolant when you cold start your engine?

 

Nope, I'll check tomorrow morning, but as far as I can tell its not burning coolant. Wouldn't the exhaust be a different color if I was?

The SES light hasn't been back after another day's worth of driving... still running rough, temps in the 60's.

 

No coolant in the exhaust. One thing I did notice, as I was leaving school after XC practice, the engine was still reading cold and I was at a stoplight. I herd what can be described as a vacuum cleaner sound from the engine. I hadn't noticed this before, and within a few seconds it shut off. It didn't sound bad or broken, sounded almost like a fuel pump sound but coming from the hood and I could hear it inside the cabin...