Idling when hot!!

So what's the problem? Idling too high? Idling too low? Not idling at all?

Ya' gotta help us out here ya' know?

 

I realize from the PR address and japanese'ish name that english is likely your third language, so dont take this personally, but I did not get your problem.

Please take a second and describe your Idle issue. Does it stall after a full warmup, or is it idling lower than when cold?

If you are having an erratic idle after warmup;

1. The first thing I would check are the intake gaskets between the intake runners and the block. They tend to fail on the 360. Sometimes you can see some black stuff ejected from the gasket area, sometimes you can hear the failure. If you need an image pointing them out, let us know.

2. I would also recommend checking your O2 sensors because they run in open-loop until they are up to operating temp, then switch to closed-loop. If one is sending an erroneous signal it could cause unexpected results. The SD3 would have shown O2 issues. A good OBDII reader will also provide real time O2 readings as well as other real time values that may be important. Such as TPS, Load, Etc. Note the numbers when cold, then when warm (during issue).

3. More help might be possible with a better description.

Good luck, we all hate mechanical issues, apart from the service techs.

 

Either the RH cat is blocked or the timing on the RH bank is not right.

Have you had a recent cam belt change by any chance?

So the car idles fine, but after 10-15 mins the idle picks up 400-500 rpm and back to normal again. This repeats itself every 2-3 seconds?

The engine idle is "hunting", yeah?

 

makisto; Thanks for the updated info:

Question: Does the red hot Cats happen at idle or after a spirited drive?

More possibilities:
1. You may have a COP (coil over pack) that is failing or the electrical connector to said COP that is corroded.
Q1: You said you changed the plugs. Did you notice any cracked COPs?
Q2: The old plugs, was one darker or lighter than the rest? Maybe one was "wet" with fuel?
Q3: The SD3 or OBDII should have reported misfire on Cyl X if there was a misfire (at least on 430s they do), have you hit it with an OBDII?

2. Sticking or otherwise failing FI. If you have a failing FI it might be fine until the car warms up, then stick open or closed, each causing different issues.
Stuck Open: Too much fuel, misfires, fouled plug, red hot cats (cat burning the unburnt fuel), exhaust on one side smells like a harley davidson (unburnt fuel)
Stuck Closed: Lowered Idle RPM, Rough running engine (on a V8, it would not have a big effect), Missing sound, slower revving without load, loss of HP.

3. Electrical load issue.
Q1: Try turning on your headlights during the issue and see if it makes it worse.
Q2: Is your battery healthy? Always starts car?

4. You mentioned you rebooted your car and went through the re-learn procedure, or the like using the SD3. Can you confirm you reset the entire electrical system and did the re-learn procedure? Make sure you have all of your CODES first!

 

I'm with trent on this one. I'd pull the plugs and check if any difference in color/ash, etc. I had a couple of coil packs go on my car and the SD did not recognize them.. apparently only fired perfect at higher RPMS...

 

Just so you understand. The glowing Cat is most likely a sign of unburnt fuel coming from one or more cylinders. The catalytic converter is igniting the fuel and trying to burn it off. This, as suggested above can be due to a number of things and certainly a faulty coil would be high on the likely list.

You haven't mentioned a Slow Down light and if you don't have one showing you probably should. The engine slowing down and cutting out could very well be the management system cutting off the fuel supply to that bank (to prevent a fire). Once a Cat reaches an excessive temperature the system will cut fuel.

If you're not handy with car mechanics DIY you could bring the car to an independent mechanic. Problems with spark plugs and coils are much the same with all cars so an independent who had never seen a Ferrari before should still be able to assist you, find the problem cylinder(s) and then maybe diagnose from there. If you/he suspects a faulty coil you can always swap it over to the other bank and see does that Cat then start overheating.

Take care and don't drive the car if you can avoid it. You may have only a relatively minor problem but it could cause a big problem before too long.

Best of luck!

 

Mistiko,

You have the typical symptoms of having a failing Fuel pump which can't put enough pressure in the fuel circuit anymore. Fuel is delivered by two separated fuel pumps, one for each engine bank.

If one of your cats are glowing red, it means that one bank is seriously running lean. A bank not having enough fuel will run very lean and heat seriously the cats - too much O2 and not enough fuel (as well as heating seriously the engine bank).

Don't use your car anymore as you risk serious engine damage and get your fuel pump checked.

Let us know how it goes. Good luck

 

Running lean can burn cyl internals (pistons, sleeves, valves) but it will have a lower EGT. The lean damage is usually from knock, excess oxidizer causing lower heat capacity (less cooling of cyl), and/or excess oxygen enabling the metal to burn once the cyl temps reach that threshold for the metal involved. Everything burns at some temp, including metal as long as you have oxygen available. In a rich situation there is no oxygen left, only hydrocarbons. Also a slightly rich mixture will cool the cylinder.

Maximum EGT is at Stoich 14.7:1 air:fuel (enough air is provided to burn the fuel). Lean is colder, as is rich. This is a common misconception.

If the mixture is too lean or too rich to prevent combustion, then you will have unburnt fuel in the catalytic converters, which will burn in the cats, excessively heating them up. I dont know how lean the 360 engine will burn, but I have heard of 65:1 burning in specially designed engines.
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Not a problem, thanks for clearing that up. I would also pull the plugs and go from there mate.

Good luck and let us know how you get along.

 

Have you got any news from your shop? Please let us know how it goes and what was the root cause of your issues.

Good luck!
Stef

 

Might not be the MAF, could be a fake out. When you disconnect the MAF the ECU has to switch from closed-loop to open-loop, and it basically ignores the regular inputs. So if you have a bad input; MAF, O2, EGT, etc, and then unplug the MAF, the defective sensor or bad reading due to wiring, etc, could be ignored.

1. Swap the MAFs. Then repeat the test.
a. If the issue follows the MAF, you have a MAF issue.
b. If the issue stays in the passenger bank, you have another failed sensor. I would check the O2 and EGT (I am assuming the 360 has a RGT, if not 1000 apologies). You can check their reading from an OBDII reader with "live data" capability. Many auto shops will loan you one, for even a day or so for free. But just buy a good one with live data capability.
I have the "Equus 3130 Innova Diagnostic Code Scanner with Live Record and
Playback Data Capability" for $140ish (no affiliation, not a sponsor of FChat). I am sure many are as good.

2. If 1.b shows a sensor issue, you can also swap that sensor and make sure the issue follows the sensor from bank to bank. Then buy a replacement. This bank t bank swapping only works because the 360/430 has two complete ECUs, where most cars have one. So take advantage of it.

3. You can also read the MAF values from the OBD2, it reports both MAFs almost side by side, so you can see if one is reporting a crazy value.

4. You might also have a wiring / connector issue at a sensor or wiring harness major connector causing this issue. Known issues are the ground harness, any harness under the alarm siren module (which can drip acid on the connectors under it from its battery). I would also check any connector between the sensors and the ECU, as well as the ECU connector itself. Inspect with a bright white LED light and look for moisture, corrosion, discoloration, small animals, heat damage, melted wires, Elvis or anything else that may seem strange.

Keep us posted, without your detailed reports we cant help!

 

I agree with Trent above as regards the improvement when disconnecting the MAF - if could well have the effect of forcing your ECU into open loop. In open loop your system reverts to it's "factory" mapping and ignores warning inputs such as the one that is probably warning your engine management that "your cat is about to go on fire".

The 360 does indeed have the EGT sensors and they and their little ECU units are prone to failure but in this case the Cat is glowing so it's likely not a failure as much as a correct warning signal being sent.

 

Hi guys,

I have the same issue, idle is going down 300-400 RPM for 2 seconds than up when car is hot. SD2 says left MAF. Cleaned up both ,issue still there ,now i'm gonna try what you guys mentioned about swapping or reading MAF data while SD2 connected. But i feel it's not the problem.

My car has the stock exhaust but the previous owner removed the cats.
I will work on this over the week end and keep you guys posted.

 

A good OBDII reader will read both MAF and O2 values on my F430. If thats easier than finding a SD2.

Yes, swap MAFs, easy test.

 

I have a pretty easy access to an SD2,but thanks for the info.
Are you from Indialantic,Fl?
I'll be there around sept 10th.
You guys have a great Starbucks by the beach! though.

 

Yes I live in Indialantic. The Starbucks at 5th Ave and the Boardwalk is very nice, especially since it is populated with ladies in swimsuits most of the season. I think they are extra friendly there as well. Now stop hijacking threads...