8.1 GI-E Rough Idling and it does not reach max RPM

[xixp]

Hi,

Port engine starts right away but there is an small vibration at idling (Stard board engine idles very smoothly) and when throttle is hit engine hesitates for a second and it revs up but it cant go over 3500 RPM under load (It used to reach 4500 RPM). Fuel consumption at any RPM has increased.

Engine has 150 hours,I thought about a fuel issue but I did not find any water in the fuel filter when I replaced it (that was my first action). Plugs were replaced at the 100 hours service.

I tried pouring some SeaFoam in the new fuel filter (Besides putting the rest in the tank) without any improvement but I haven't run the boat in the water because I'm afraid I could damage the engine. Should I try to run it for a while to allow the cleaner in the tank to kick in?

Gauges dont not show any abnormality .They show the same values (Temp, oil pressure,etc) than the stardboard engine, no alarms.

Any ideas before calling the dealer?

 

[Don S]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Have you checked the fuel filter for water? Not just change it, actually empty the old filter out and look for water and contamination.
When was the last full tuneup, cap, rotor, plugs, compression check.
If that has been done, then you need to get it hooked up to a diagnostic computer. That's what they do, help you diagnose problems.

 

[xixp]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Thanks Don

I put the filter content in a transparent container and I did not find any water.
I thought that with 150 hours cap and rotor did not need to be replaced (plugs were changed at 100 hours). Furthermore I thought that these engines did not use rotor nor cap because they have individual coils on top of each plug.

I'm concerned about the compression, I know that some people had issues with the he gasket even with a lot fewer hours in the engine.

I will schedule a service call to let the dealer diagnose the issue then.

Thanks

 

[jerryjerry05]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Profile,location?You might be close to someone who can help.
A compression test then a visit to the diagnostic machine?

 

[xixp]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Update,

Update.....

I removed the plugs and for my surprise they did not look like they had been replaced at 100 hours. Rear 4 plugs had severe carbon deposits and they even were painted in red like the engine so I guess they were the original plugs. (Another bad dealer experience under my belt...). I went to NAPA and bought a set of NGK TR4 that are recommended by NGK as a valid replacement until I get the same AC Delco 41-983 plugs that were installed in both engines. The engine runs better than ever!! It consumes less fuel that the other engine and runs perfectly at any RPM!!
Ive ordered 16 41-983's to replace the plugs of both engines at once.

 

[jerryjerry05]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Time to go postal on the dealer!!!
Profile? Location?

 

[Don S]

Re: 8.1 GI-E Rough Idling and it does not reach max RPM

Do the right thing, contact Volvo, not the dealer, and tell them what happened. They do not need dealers like that, and I know Volvo doesn't either.

Not sure why jerry wants profile and location so much on evey thread, without the proper equipment and experience someone in your area may only know as much as (or less than) your dealer. And for this post, it doesn't matter where you are located, the problem is the same rather you live in the US or Siberia.