355 unwilling to rev out

When i bought mine i had several ecu problems. first one was cutting out 1 bank all over. i bought another second hand and that had a 7k rev limit on it. dont know why, seller couldn't help, sent it away to be remapped, came back the same. sounds like your problem.
i tried a friends which worked but had intermittent slow down lights come on, eventually bought another unit that worked perfectly.

i believe them to be a little delicate with an ability to show all sorts of problems!

 

Mark, make sure to run on metal cat inserts in he big shells.
Also I've seen melted metal cats in the Y clogging the way on one side.
I know the factory omitted these little converters since 1998/1999.

Another car had bad performance on the dyno because the mechanic didn't see one cam out of adjustment while doing the engine out service.
She lost 30 hp because of this mistake. Proper adjustment in another shop fixed the issue later.

Injectors: Dirty fuel can foul some of these.
Some companys offer to clean them by ultrasonic bath.

Other known part for responsible for kind of weakness over time: air mass unit.
In your 5.2. it's just one, so you're lucky.
Although some people say you can clean it using carburator cleaner spray, other mechanics say these parts are to replace from time to time.
You can recover them only for a short period of time.
(lambda sensors, we know, need to be replaced at 80.000 km)

First I would read out the motronic to see all components & sensors o.k.

cheers,

cinque

 

Hi Mark, I would check the operation of your exhaust bypass valve, it could be its not opening fully under full throttle conditions and restricting the exhaust flow.

 

Hi Mark

Definitely sounds like a flow restriction. I had a simialr issue on one of my old cars, but that was an intake restriction rather than exhaust.

I think first up, I'd wire open the bypass valve and see if it will rev out then. It'll probably throw up a warning light as the Cat ECU's won't get hot enough but it should allow you to see if that is the flow restriction.

Next up, I'd pull all the intake plumbing apart and make sure there's no blockage.

Failing that, I'm unsure...

Drew

 

On your older car, what kind of intake restriction did you find?

 

+1 on the injector testing/cleaning.

However, DO NOT used carburetor cleaner on the MAF. CCR sells a special cleaner for MAFs. Carefully remove it from the air intake hoses and use the entire can - spraying from both front and back (you're primarily cleaning the small hot film sensor in the middle of the intake). Let it AIR dry and then reinstall. While you're at it, get some CCR electronic cleaner and clean the MAF and idle regulator electrical connections. Hell, clean all the electrical connections you can get to, including the ECU connections.

You might also want to try using your battery disconnect. Shut the battery off for 5-10 min and then turn it back on. Start the car with ALL electrical items off and let it idle for about 15 min. The ECU will re-learn its parameters. This is really better for idling issues, but in the cases it certainly can't hurt anything.

 

I regulary disconect the battery on my car and have read on this forum there is no need to let the car idle for 15 minutes, I drive mine for 15 minutes not exeeding 40 MPH and this appears to work ok on mine.

I personally dont like my car idleing for that lenght of time because of tempatures building up etc.

This also is a cure for cat temp re-learn too and puts the slow down light out too.

 

It was an old MR2 turbo. They use a variable intake system with dual runners and butterfly valves. Did some upgrades but forgot to connect the intake trigger to the new ECU, so it was running on half the normal intakes.

Took me a while to figure out why the intake temps were rising but the car wouldn't rev at all!

 

Interesting, both the OM and WSM specify to let the car idle with all electrical equipment off. I don't see how the ECU could re-learn its parameters under the constantly changing conditions of actually driving the car. But, I am certainly NO expert.

 

Short answer - No. But, I supposed you could pull the valve covers and somehow wedge yourself up between the gas tank and engine to see how the factory marks align, but there is NO way to do it properly with a degree wheel.

 

Sounds like coil packs to me.

 

Neil:

You're a genius! I didn't even think of those, but I have heard of them going in other cars and causing the same symptoms. Great call.

 

sounds like and injector/fuel problem. but could posssibly be a 02 sensor or some other sensor putting it in limp mode.

 

Worst thing to do is substitute parts without knowing what the fault is, you could replace a lot of items and still not find the cause or worst case even introduce a new fault, new components can sometimes be faulty too! Someone posted above, but first step is to get the car hooked up to a SDx/OBD2 code reader machine and read the codes. When you have onboard diagnostics it's best to use it. If no faults are reported that's when it gets a bit harder and reverts to good old mechanical/electrical know-how.

If you don't want to go to a dealer, you can buy one yourself and do it that way. I got an OB2 reader a while ago but haven't got round to hooking it up properly simply because there is no OBD connector on our UK 355's. All it needs is a simple mod/harness making up but haven't had the time and no fault on my 355, just curiosity!

Do a search, there are some recommendations on here for DIY OBD readers.

 

Mark, The knock sensor controlls the timing and if this has an intermttant fault you may not be getting full advance, What fuel are you using, the same thing will happen if your getting detionation (pinking), the knock sensor will retard the timing to prevent damage.

I use Shell V power or BP in my 355, I have heard Tesco's 99 octane is ok but Im not a lover of supermarket fuels...

 

That fact right there could very well be your problem! Buying Dave's kit will be a very, very wise purchase. IMHO, this kit is going to become SOP on all Ferraris of this generation in the near future. It's absolutely amazing the difference this kit can make. I have almost completed installing mine and there is an amazing, real, and tangible difference in the way the car runs, idles, accelerates, etc..and it most certainly is not psychosomatic. I can't stress highly enough the difference this kit can make in the way your car runs. Dave is truly an amazing and talented engineer.