Hard start 87 328-need advice..

It is strange that it would consistently start from cold but not from hot with a draw on the battery. If there was a draw causing a starting issue I would think you would see it with cold starts, not hot. If there was extra draw while running it would decrease battery power and letting it sit until cold would not increase the battery voltage, unless you have it on a battery tender.

Have you checked the battery voltage when cold, when the car is running, and again when it is not starting after it is hot?

 

Brand new battery was installed with the new engine. Had the battery checked also.

 

I am betting on the accumulator. Can you take it back to the shop that installed the engine and have them identify/correct the issue?

 

I will take it to the shop and have it checked. Thanks!

 

More generally, you should have the system fuel pressure after engine shutoff checked. If the fuel pressure (wrongly) drops below ~3 bar after engine shutoff, this can be caused by a bad accumulator as Dan suggested, but it can also be caused by a bad fuel pump check valve or bad seals in the fuel distributor pressure regulator.

 

Greg,

The connectors for the flywheel sensors are in the left rear wheel well. There's a connector for each sensor, and there is a larger connector for the harness (it mounts through the framework for the side intake to the oil cooler).

To gain acces, you will need to lift the rear of the car, remove the left rear wheel and wheel well.

I recommend cleaning these connectors and checking for slack (each electronic tap should be firm to make good contact). I also recommend cleaning the other larger connector at the same framework. It sounds like you have an intermittent electrical issue that is temperature biased. Cleaning these connectors may help.

Same goes for the aforementioned connectors in the passenger footwell.

Some insight can be gleaned from my RobzWorkz#7 (it's about the cooling system, but has pics of the wheel well area and the sensors):

http://www.ferrarichat.com/forum/showthread.php?t=325346

 

I agree with this. It is called the residual pressure test. Be sure your shop knows about this. It is a very common test for the Bosch K-Jet.

 

Greg,

Look at Steve's post (#22) and try the testing he indicated. I believe that is the Steve post you were referring to.

Good luck.

 

Sorry to interrupt your thread. We have kind of the same head scratching problem and there are some great guys on here with much knowledge about our cars. I hope you can find the problem. Best of luck and have a safe and Happy New Year! Cheers Pat

 

This is definitely an area to look at. It's a false assumption to assume the sensors and wiring are good because the car runs OK.

During starting the overall supply voltage is lower owing to starter motor load and crank speed is low, so if the signal from the sensors (which is a low voltage anyway as they are simply coils) is lower than it should be, nothing will work.

Each sensor as its own inline connector as well as the common round one on the bulkhead, so these need to be checked as well.

 

well, we`re into 5 pages now...
to find a solution, you need a systematic approach here

as for all the symptoms you described sofar and after everything you have already done,
I think there are only two failure possibilities :


1) you don`t get +12V power neither to the coils nor to the microplex ecu
(both coils and the microplex ecu are seperately +12V fed by terminal 15 of the ignition switch)

2) there is no signal from either the rpm sensor or the tdc sensor to the microplex ecu



to check for power, do the following:
in the no-start situation...

1a) measure power at terminal 15 of both coils to ground while ignition on
(you should see 12V - if you see 0V, the ignition switch is faulty since it feeds both coils)

1b) verify you measurement by checking if you see +12V on pin 13 of the 25pin connector to the microplex ecu
(you will measure the same value like on the coils ! since the +12V source also comes from the ignition switch terminal 15)

IF the above measurement checks out o.k. (and you really see +12V), the ignition switch is not you problem -



Now to check the sensors, do the following:
in the no start situation...

2a) for the tdc sensor, check the ohm value bwteen pin 1 and pin 2 on the 25pin connector of the microplex ecu

2b) for the rpm sensor, check the ohm value between pin 3 and pin 16 on the 25pin connector of the microplex ecu

you should measure a value of 650-1000 ohm on each sensor
(the 328 engine will not start nor drive if either sensor fails since the microplex ecu needs a signal of each -
if the ecu does not "see" a sensor, the culprit is either the sensor, the connector described in previous posts or the ecu itself)



before the above checks have not been executed, it will be hard to examine the problem any further in a meaningful manner

Happy new year !

 

no problem...start from scratch now
and be glad that you`re busy...good music btw

ohm measurement should work without key/ignition on

both is possible...(if sensors, coils, ecus fail sporadically it is mostly due to heat...and work fine after cooling down...)
so in this case if you`re lucky, it is "only" a loose connection somewhere - power and/or signal

the idea of the above measurements is to exclude parts/connections/routes
and shift probability to others


the nice things about these problems are that we all learned something after the solution was found

.

 

Just a quick question,how old and in what condition are the HT leads?
2 years ago l had a similar problem only that l wasn't losing power completely,rather l would only lose one bank,but it was intermittent and it would only happen while the car was hot..the bank would drop then comeback on then drop and come good as soon as the car would cool down.I checked everything complicated first,tested the microplex as well as the sensors,checked the ignition switch and all the relays,even replaced the fuel filter just in case it was a blocked filter..replaced ignition modules but the problem was still there.Then l decided to remove the ignition leads and test them individually..Three out of the four leads serving the front bank were faulty but would get worse as they got hotter.Removed and replaced all the leads and the car hasn't missed a beat since.It's the only problem l've had with the car in almost 5 yrs of ownership.
Only thing l really need to address on the car is a rear bank cam seal thats leaking.

 

Greg,

There aren't many parts in the starting circuit and it looks like you have covered them all. Is there any tester/device that you can connect to the round data link in the engine compartment that connects to the injection system that would give you any pertinent information.

I found this link on how to test the Ferrari 328 Ignition ECU. Maybe this would help.

http://ferrari.cdyn.com/carl_rose_docs/Ferrari%20328%20Microplex%20ECU%20Testing.pdf

Mark

 

I searched and couldn't find anything more about your alarm then what I had sent you previously. I did find somebody who talked about removing that alarm. What they said was that typically a wire was cut and then two wires were spliced in between the cut, maybe a relay or some other isolating circuit. They said follow the cut wire and find the two splices, remove them and splice the wire back together. If you do that one at a time, I suspect you will eventually remove the alarm from the system. Just do one at a time and test that you didn't make anything worse and go to the next.

Mark

 

Greg,

I'm a little late to the party here, but I had a similar problem with an alarm that had been installed in a Mondial QV that I owned. I found a local alarm shop that had been around for a long time, and the owner was very familiar with the old-style systems. I took the car to him and for not a lot of money, he went through the car and removed all of the alarm connections and re-wired everything back to stock. I had previously solved a bunch of problems by removing a corroded ground switch and negative battery cable, but removing the alarm entirely solved the intermittent no-start problem.

My suggestion -- start calling around to some alarm shops in your area, and hopefully you'll find someone who installed the old Mirage systems. Rather than guess at what you are doing, and ending up disconnecting something that will end up disabling your car permanently, take it to someone who understands alarms and can remove what needs to be removed. They might even be able to save your remote door lock system for you.

Just a thought.

p.s. Remember Occam's razor -- the simplest solution is usually the correct one. If you think it is related to the alarm (and you've posted lots of good reasons to think it is the alarm), start there and eliminate that from the equation before you go off into other areas.

 

Greg,

I just found this on the m9000 alarm, check to see if this looks like it might apply.

The alarm has the following wires:
org - siren; org/blk - lights; prl - hood lock; wht/red - started key; wht - starter motor; tan - trunk (no wire connected); red - +12vdc; blk - ground; blu - lock switch; blu/blk - lock motor; grn - unlock switch; grn/blk - unlock motor; red/blk - polarity; sensor port; wht - +trig; yel - -trig; grn - -trig; gry - led; pnk - valet; blu - ign; brn - disarm;