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Discussion Starter #1
I have a strange cold start pr

I have a strange cold start problem with my 1985 308QV. Whenever I start the car when the engine is cold, I have the following problem. For the first 60 seconds the car runs great and the idle is at 1,000 rpm (according to the manual 1,000 rpm is normal). After about 60 seconds the idle goes down to 500 rpm and the engine sounds as if it is missing and about to stall (it never does). After about 10 minutes the idle magaically returns to 1,000 rpm and the engine sounds normal again. What is my problem? Please help.
 
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Discussion Starter #3
That was not the type of respo

That was not the type of response I was looking for. What causes you to say "YIKES"?

Ken
 
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Discussion Starter #4
Ken,

the type of problem yo


Ken,

the type of problem you describe is going to take hands on analysis imo.

To even begin to be able to guess with any degree of hope of getting close, one at a minimum needs to know which system is the culprit, ignition or fuel. And even then on the internet it's stil a wild crapshoot imo.

If I had to make a wild guess, I'd say look at the electrical portions of the ignition systems first.

Regards, JRV
 
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Discussion Starter #5
Hi Ken,

After you start t


Hi Ken,

After you start the car it idles at 1000 RPM? That is not normal. Mine goes through a warm-up period at about 2500 RPM for about 2-3 minutes. Then it drops to 1000 RPM and idles there. As I understand it this is the normal process to heat up the cat.

I think what JR is saying is that the "problem" can not be pin-pointed based on the limited information given. It doesn't sound normal, but no diagnosis can be made this early on. JR is not one to take wild shots in the dark when confronted with a car that is not running correctly. That would only waist your time and possibly money. There is a logical process that you must go through in order to solve your issue. You can't get to point E without going through points B,C, and D.


Lets start with what/where should you start looking?


JL
 
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Discussion Starter #7
Ok, the fact that the rpms are

Ok, the fact that the rpms aren't climbimg to 2500 indicates that you aux. air valve is stuck closed. My AAV was stuck before and wouldn't go into high idle 2500 or so. It starts and goes to 1000rpm. Now onto the bogging issue. Could be many things but I will try to help isolate some ideas. The AAV adds extra air during cold start since the CSI is spraying and the WUR is in its lowest pressure setting(richest). To make a long story short it could be too rich causing the car to bog since it isn't getting its extra air. Idea #2 WUR (warm up reg.) when the bimetallic strip isn't functioning properly/resistance is out on the WUR can cause bogging on cold start and when you give the car gas it is very reluctant to take it. It will bog more then the rpms will rise slightly. Pressure testing will show if it is in the WUR. It sounds like first check your spark on all wires with a timing light, then the AAV, remove it, clean it, bench test it, replace it if is not functioning correctly, then move onto fuel pressures. HTHs.
 
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Discussion Starter #8
Thanks guys. I have already r

Thanks guys. I have already replaced the coils, so I now they are not part of the problem. One questions I have is should all 308QV idle at 2,500 upon start up, or just the earlier carb'd cars?

JRV: I was not trying to be a smart ass, but I took your response to indicate the repair would require $$$$$$$$$$$$$$.
 
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Discussion Starter #9
Ken,

ALL 308's have the


Ken,

ALL 308's have the high idle.

Didn't mean to scare you...not big $$$$$, but almost impossible to pinpoint via internet. Believe me, I would love this forum to be a miracle worker....., but I'm the first to see it's limitations.

Sounds like everyone has you on the right track though.

Regards, JRV
 
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Discussion Starter #10
OK. My Aux air valve seems to

OK. My Aux air valve seems to be working fine. What else could cause my idle to be only 500 rpm's for the first 10 minutes?

Also, how can I simulate a cold start once the engine is warm? I will need more than 5-10 minutes to find the problem at hand.

Thanks.
Ken
 
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Discussion Starter #11
Ken,
This is a pretty straigh


Ken,
This is a pretty straight forward problem to diagnose, but you need to start at the beginning with the basics. I believe Rich spelled it out pretty clearly and accurately...

With any CIS problem, the first step is to always check and verify the cold and hot system and control pressures. Without knowing the pressures (hot and cold), you're pretty much waisting your time...Bosch, as well as other manufacturers makes a gauge set, with the various adapters needed, to check these pressures. Once these pressures are known, the operational problems with our car become clearer as to the direction to persue.

The second step, is the check and verify (as discussed previously) the heater operation in the warm-up regulator. Once verified to be correct, then the aux air valve, air tubing, base idle setting and throttle stop position need to be verified.

Last, but not least...the sensor plate height should be verifed, and the warm CO/HC mixture should be set, even if the car runs "fine", once warm.

Before any CIS diagnostics are done, all ignition components and vacuum hoses should be verified for integrity...

Regards,
David
 
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Discussion Starter #12
David has a valid point, all d

David has a valid point, all diagnosis should be methodical and structured. First, you must understand how things are supposed to work, then assemble relevent data and test equipment. It is very easy to go off on a tangent and totally miss the obvious. That's why we pros can charge the big $$! Been there and done that.
Having said that, the warm up regulator on a 328 recently was at fault and gave a poor cold start similar to yours. It showed up when the pressures were checked during warm up, the control pressure rose too fast causing a lean condition during warm up. Replacement with a Porsche unit (Ferrari being unobtanium) fixed and car ran better than ever.
 
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Discussion Starter #13
I'm not a fan of substitut

I'm not a fan of substituting WUR's from one make or model to another (especially K Lambda equipped cars). The old WUR's can be rebuilt in most cases. Give a call to Frank @ AW for details.

Regards, JRV
 
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Discussion Starter #14
Thanks guys. I will be testin

Thanks guys. I will be testing all pressures next weekend when I get access to the gauges and the assistance of my mechanic.
 
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Discussion Starter #15
Yes AW Imports has hard to fin

Yes AW Imports has hard to find parts.
Now if they can't help locate one I found one at
allimportedparts.com
It is in stock and around $400. Not meaning to take anything away from our sponsors just thought I would mention it.
Their # is BH008088.
 
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Discussion Starter #16
Is there a cold start relay on

Is there a cold start relay on your car? I had a similar problem with my TR (1986) and when the relay was replaced, the car started fine and have not had any prbolems since.

Just wondering
 
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Discussion Starter #17
Brian,
That is interesting ab


Brian,
That is interesting about not being able to obtain a warm up regulator for a 328; was this through FNA? It has been superceded by a newer version, but Ferrari UK supposedly stocks them.

Part #119825 $525(!) supercedes previous #118585 My mechanic found mine needed replacing (87 328 GTS) and I believe he got it from Ferrari UK. Bosch says on their website that the Bosch part number is 0 438 140 132
 
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Discussion Starter #18
The Porsche spec one has the s

The Porsche spec one has the same warm up curve as the original but at $115 was considerably less, the customer has been delighted with the better start and running characteristics. FWIW.
 
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Discussion Starter #20
OE Ferrari/Bosch warm up regul

OE Ferrari/Bosch warm up regulator # 0 438 140 132

Porsche 911/Bosch # 0 438 140 090 list $567.65
cost $180.50
 
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