When to replace injectors?

[ionofchios]

Have e86 3.0si with 185,000 km on it. Is it worth replacing the injectors? I don’t really have any symptoms that might mean they are bad, other than maybe slightly lumpy idle for about 20 seconds when starting from cold. Wondering if injectors are kind of binary in their failure mode and you don’t touch them unless you have good reason, or are they something you should always replace after certain mileage, as they degrade gradually?

 

[skelters]

Any error codes?

What's the service history like?

When was it last serviced?

What fuel are you using?

 

[ionofchios]

Any error codes?

What's the service history like?

When was it last serviced?

What fuel are you using?

No codes.

Service history quite good; for example, I can see that plugs were done 30k ago. I’ve been servicing since I got it, meaning regular oil change, etc. I did stick a bottle of Redline SI1 through it a while back.

98 e5.

 

[mmm-five]

My M had over 250k km on it when we decided to do an rebuild (and then decided to just replace it with a 70k km engine instead)...and in the 240k km I had it I’ve never needed to replace injectors. Good fuel usually helps keep them clean & efficient.

 

[skelters]

Don't remember hearing of issues with injectors on any si engine.

No errors, no symptoms of the injectors being faulty, serviced etc.

Coil packs?

 

[BRC]

As you've suggested the injectors are pretty much a binary thing, they either work or don't. You'd soon know if there was a failure.

 

[Machine monkey]

I have a set out of my 2003 3.0l on 65k
Only reason I changed was I have fitted a turbo and needed more flow.

 

[Migizi]

I had a similar issue, and then performed the valvetronic adaptation reset with INPA and the lumpy idle cleared up.

Try the valvetronic adaptation reset first
then use a high quality fuel cleaner - I use Techron

 

[ionofchios]

I had a similar issue, and then performed the valvetronic adaptation reset with INPA and the lumpy idle cleared up.

Try the valvetronic adaptation reset first
then use a high quality fuel cleaner - I use Techron

Thanks, I’ll try that.

 

[ionofchios]

What about coil packs - is that the same, meaning you don’t need to touch them unless you have symptoms?

 

[Limonge]

I had a similar issue, and then performed the valvetronic adaptation reset with INPA and the lumpy idle cleared up.

Try the valvetronic adaptation reset first
then use a high quality fuel cleaner - I use Techron

Thanks, I’ll try that.

Hello, did you give it a try? My car idles a little rough when cold started (just a little bit, you can barely see the needle shaking, and the sound if you pay attention to it)

If it's worth it I'll try it