• Ciao Guest - You’ve landed at the ultimate Guzzi site. NEW FORUM REGISTRATIONS REQUIRE EMAIL ACTIVATION - CHECK YOUR SPAM FOLDER - Use the CONTACT above if you need help. New to the forum? For all new members, we require ONE post in the Introductions section at the bottom, in order to post in most of the other sections. ALWAYS TRY A SEARCH BEFORE STARTING A NEW TOPIC - Most questions you may have, have likely been already answered. DON'T BE A DRIVE-BY POSTER: As a common courtesy, check back in and reply within 24 hours, or your post will be deleted. Note there's decades of heavily experienced Guzzi professionals on this site, all whom happily give endless amounts of their VALUABLE time for free; BE COURTEOUS AND RESPECTFUL!
  • There is ZERO tolerance on personal attacks and ANY HYPERLINKS to PRODUCT(S) or other competing website(s), including personal pages, social media or other Forums. This ALSO INCLUDES ECU DIAGnostic software, questions and mapping. We work very hard to offer commercially supported products and to keep info relevant here. First offense is a note, second is a warning, third time will get you banned from the site. We don't have the time to chase repeat (and ignorant) offenders. This is NOT a social media platform; It's an ad-free, privately funded website, in small help with user donations. Be sure to see the GTM STORE link above; ALL product purchases help support the site, or you can upgrade your Forum profile or DONATE via the link above.
  • Be sure to see the GTM STORE link also above for our 700+ product inventory, including OEM parts and many of our 100% Made-in-SoCal-USA GTM products and engine kits. In SoCal? Click the SERVICE tab above for the best in service, tires, tuning and installation of our products or custom work, and don't miss our GT MotoCycles® (not) art on the BUILDS tab above. WE'RE HERE ONLINE ONLY - NO PHONE CALLS MADE OR RECEIVED - DO NOT EMAIL AND ASK QUESTIONS OR ASK TO CALL YOU.
  • Like the new V100, GuzziTech is full throttle into the future! We're now running on an all-new server and we've updated our Forum software. The visual differences are obvious, but hopefully you'll notice the super-fast speed. If you notice any glitches or have any issues, please post on the Site Support section at the bottom. If you haven't yet, please upgrade your account which is covered in the Site Support section or via the DONATE tab above, which gives you full site access including the DOWNLOADS section. We really appreciate every $ and your support to keep this site ad-free. Create an account, sign in, upgrade your account, and enjoy. See you on the road in 2024.

P8 ECU and idle trim screw info

GTM®

Administrator
Staff member
GT di Razza Pura
Joined
Jul 1, 2009
Messages
15,055
Location
Malibu
For those who need this info, Trim screw direction for lean/rich.

P8 AF Screw

Actual P8 Manual Download below.
 

Attachments

  • P8-injection-manual.pdf
    2.4 MB · Views: 147
Re: P8 idle trim screw info

Never personally tweaked this adjustment, although I still have one Guzzi ('97 California Anniversary) that has the P8 computer.

But I have been warned to use a screwdriver with an insulated shaft. Apparently, you can do some damage if you short the adjuster on to the side of the box. Can't verify this, but wish to pass the warning on.
 
Re: P8 idle trim screw info

kiwi dave said:
But I have been warned to use a screwdriver with an insulated shaft. Apparently, you can do some damage if you short the adjuster on to the side of the box. Can't verify this, but wish to pass the warning on.
Dave, my buddy Claudio of LongWalk.it was here for the last few weeks, and he constantly tweaks this as fuel quality/pre-detonation demand. He uses the all metal screw driver from the OEM tool kit, so not saying that what you say is incorrect, but he's had no issues to date.
Unrelated, I burned two new EPROMs for him to try and combat the poor fuel in South America... so I can now burn P8 EPROMs for anyone reading this/in need.
 
Re: P8 idle trim screw info

Yeah, that's why I mentioned that I can't verify it. In fact I don't want to verify it, so I would use the insulated screwdriver if I ever get in there.

Perhaps your buddy Claudio has a real steady hand. Seems strange that he had to constantly tweaks, why would you have to keep chasing the setting?
 
Thanks Dave

This is excellent reference material, much appreciated. My California Stone is all over the workshop floor at the moment. I'll be tweaking the trim screw using a CO gas analyzer when its back in one piece. The system is the same as on many of the Fiat and Lancia vehicles I've worked on in the past. Its pretty simple once you get familiar with the components. My bike is a later version with the fuel filter inside the tank. Its easy to miss this when servicing the bike because you can't see it so I'd suggest anyone working on these replaces the filter first up. Its a tiny filter and you'll hear the relief valve in the pump actuating when the ignition is turned on if its restricted. Mine hadn't ever been changed in 10 years of use.

Cheers

Ian Jowsey
Hobsonville NZ
 
ian-jowsey said:
Thanks Dave

This is excellent reference material, much appreciated. My California Stone is all over the workshop floor at the moment. I'll be tweaking the trim screw using a CO gas analyzer when its back in one piece. The system is the same as on many of the Fiat and Lancia vehicles I've worked on in the past. Its pretty simple once you get familiar with the components. My bike is a later version with the fuel filter inside the tank. Its easy to miss this when servicing the bike because you can't see it so I'd suggest anyone working on these replaces the filter first up. Its a tiny filter and you'll hear the relief valve in the pump actuating when the ignition is turned on if its restricted. Mine hadn't ever been changed in 10 years of use.

Cheers

Ian Jowsey
Hobsonville NZ

Ian,

Your bike doesn't use the P8 ECU. It uses the 15M. The "trim screw" can only be adjusted electronically with software on the 15M. Todd has an excellent sale on the software at this time. See the Store tab.
 
Cheers John

That explains why I couldn't find the adjuster when looking for it last night! The atmospheric pressure sensor looks different too but the rest of the components apart from the fuel pump and filter arrangement seem to be the same or similar.

Regards Ian :idea:
 
ian-jowsey said:
Cheers John

That explains why I couldn't find the adjuster when looking for it last night! The atmospheric pressure sensor looks different too but the rest of the components apart from the fuel pump and filter arrangement seem to be the same or similar.

Regards Ian :idea:

With the 15M, the pressure sensor is internal to the ECU. Just forget everything mentioned for the P8 as it doesn't apply to your bike. The only useful information is the value of shared sensors. Even the TPS settings for the bikes are different.
 
I got it running .... was starving fuel .
I cleaned the petcock and replaced few fuel lines and she started right away.... fuel pump still noisy , have to figure out why.
thanks
 
fuel pump still noisy , have to figure out why.
thanks
Good to hear, and replace the pump. It's likely full of crud, and it's non-rebuildable. I have some alternates listed in the Archives (tab above).
 
Interesting reading ,got me wondering about fuel filters and changing them . What's the general opinion on how long they go before needing changing . Manuals invariably quote service intervals for air filters but here in Scotland I have yet to come across an air filter that's choked ( too damp for dust )and I doubt that my 1100i Cali has had a fuel filter change in years ( owned by me for 1 year )
 
Interesting reading ,got me wondering about fuel filters and changing them . What's the general opinion on how long they go before needing changing . Manuals invariably quote service intervals for air filters but here in Scotland I have yet to come across an air filter that's choked ( too damp for dust )and I doubt that my 1100i Cali has had a fuel filter change in years ( owned by me for 1 year )

Where you have clean fuel, 40 to 45,000 miles should suffice. If in an area where fuel is not so clean, then perhaps 20,000 miles. It is not so much age, but how much fuel has been filtered and how good the fuel is.
 
Back
Top