Jpdiag

I’m on a massive learning curve with Ducati diagnostics, but with a bit of determination and hopefully some of your expertise, I’m confident I can get my 998 running sweet.

I’m currently chasing a high-temperature issue. I’ve already addressed the hardware side—flushed the system with waterless coolant, changed the temp sensors, checked the water pump fins, and bled the system—but the bike is still running very hot on the gauge.

I suspect it might be running lean, as it has Termignoni slip-ons and I’m not yet sure if the ECU has been mapped to match. I’ve just got JPDiag set up to check my CO trim and ECU ID. Looking forward to learning from you all and getting this Testastretta dialed in!"

isn't running too lean ?
what are you calling very hot ?

To be specific about the heat: the bike is hitting 120°C and climbing as soon as I’m in slow traffic. This is past the point of being a 'hot' Ducati and feels like it’s on the verge of a boil-over, even after a full cooling system refresh (waterless coolant, new sensors, pump check). its a bit spluttery at low throttle speeds

Here is the confusing part with the ECU:
The previous owner gave me a spare 996R ECU in a box, but the bike is currently running what appears to be the original stock Biposto 998 ECU.

Since I have Termignoni slip-ons installed, I’m worried the bike is dangerously lean on this stock map, which would explain why it's rocketing to 120°C so fast. I’m waiting on my KKL/FTDI cables to arrive so I can use JPDiag to check the CO trim.

Has anyone seen temps this high just from a lean condition?

Is it worth even trying to adjust the CO trim on the stock ECU, or should I be looking at getting that spare 'R' ECU remapped to suit my Biposto engine?

I’ll post my ECU IDs as soon as the cables land. Thanks for the help

996r and 998 use the same mapping.
yes 120 is very hot i, the fan shall trig at 101 and 102° and maintain temp below 105 or so
usualyy the DP map is leaner than the stock map

hanks for the reply,

That is very helpful to know that the 996R and 998 use the same mapping architecture—I will definitely keep that spare ECU in mind as a backup.

Regarding the temps: I am definitely seeing 120°C+ in traffic, which confirms it's running way hotter than the 105°C benchmark you mentioned. However, I have verified that the fans are kicking in correctly around 102°C, so the electrical system is doing its job.

Since you mentioned that the DP map is often leaner, and I am currently running Termignoni slip-ons on what I believe is the stock ECU, I’m leaning heavily toward a lean condition causing this extreme heat.

I am just waiting for the KKL/FTDI cables to arrive. As soon as I am connected, I will post the specific Map ID and my current CO Trim value to see if I need to bump that slider up to get the temps down. what do you think?

co trimmer is only active in a small part of the mapping ,.
mainly below 3000rpm, you can compare at iddle the time the engine need to reach the same temp

That is a great point about the trimmer range. Since my biggest issue is the rapid climb to 120°C while sitting in traffic or moving slowly, the trimmer is likely exactly where I need to focus first.

I’ll follow your suggestion: once the cables arrive, I’ll check the current trim, adjust it, and then time how long it takes to reach the fan trigger temp at idle compared to before. This should show me pretty quickly if a lean idle/low-speed mixture is what’s causing the heat soak.

I’m also interested to see if I’m running that 'leaner' DP map you mentioned once I get the software ID

you won't see the software version with jpdiag,those old 59m ecu are very poor in giving details
you can only trust the sticker on the ecu

Thanks for the heads-up, JP. I'll take the 'A2' sticker on the casing as gospel then.

Since I can't verify the software version internally, I'm going to focus entirely on the CO Trimmer once the cables arrive. If I find it's at a low 'stock' value, I'll try richening it up to see if that tempers the 120°C spikes in traffic. If that doesn't work, I'll know for sure it's time to look for a properly flashed DP unit or a specialist remap. Cheers!

Sorted and licence now requested