Rough Idle, Loss power, Backfire

I just checked my invoice and mine is listed at !00.00 for the part. Mine is an 86 3.2

 

What you want to make sure of is the 02 you get has the right connector. Some come with a universal connector that you have to splice. I have never been a big fan of the splice for this application.

If someone has the Bosch p/n, you can cross reference or simply search on that. I get Bosch 13957, which interchanges with Audi and VW. Should be in the $50 range if someone can confirm that p/n. I have had good luck with Amazon of all places for O2's using the Bosch p/n.

Regards,
Jerry

 

Found the mother load of O2 sensors, OE by Bosch = $49.28 Yep, have one, done, I'm just gonna replace it, so I don't have to second guess!
Manufacturer: BOSCH
Part Number: 13957
Description: Oxygen Sensor
3 Wire ; Heated ; Check/Replace Interval: 60,000 Miles;O-2 SENSOR; Per Car Qty:1
Emiss Sns, Rly, Sol. and Switch

http://www.oxygensensor123.com/ShopByVehicle.epc?q=1988-FERRARI&yearid=1988%40%401988&makeid=26%40%40FERRARI%40%40&modelid=7012@@MONDIAL%203.2&mode=EG

 

A good splice crimp + heat shrink tubing is cheap, easy, and just as good as OEM. What's to worry about?

 

No need for splice with what Mike found. Thanks Mike I saved it in my favorite. I know I'll need one someday.

 

Dan, I was able to source the part for the Protection Relay, did you use the Porsche one for your 328 and all is good, that will save me $50 bucks from the horsey stamp!

OEM-92861512402 New frequency valve protection relay from Pelican Parts$93.75
http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=OEM-92861512402&catalog_description=Genuine%20Porsche%20Part%3A%20RELAY

Ferrari Mondial 3.2 QV (1987) Relay protection electrical system
61766200 KE JETRONIC FUEL PUMP PROTECTION RELAY WITH FUSE, 328/412/TESTAROSSA/MONDIAL 3.2 (NOTE) $145.25
http://www.allferrariparts.com/search.php?description=true

 

Yeah, it can be done if you are careful and know what you are doing, but, at $50 with OE connector, why bother with cut and splice? Just another place for potential electrical issue and these cars have enough without tempting the gods!!!

Regards,
Jerry

 

That is the correct part number.

 

Today I had some garage time and decided to replace my spark plugs and clean the distributor cap/rotor in hope of resolving my rough idling problems. Replaced spark plugs (gap = .024) with new NGK Iridium Spark Plugs. Also checked and cleaned distrib cap and rotors, used sand paper to clean out the carbon build up. The distrib cap behind the seats are a real challenge. Highly recommend an engine out if possible, doing this in limited spacing just kills your time but forces you to come up with ways to get it done. I found myself going to Pep Boys a few times needing special tools. Overall, it did not look too bad and I don't think this would cause my idle problems. I accidentally stepped on an extender and cracked it, so ordered a new one from Ricambi. The others looked okay and still in good condition. Here are some of the pics of what I did.
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And....? Did it help Mike?

 

After I cleaned and put everything back in, fired her up and oh boy, worst idling, back fire, stalled. Waited a few secs, started up again, now it wont start, Waited a few minutes and started her again, this time it started but still rough, it wanted to stall but did not. Finally I let it run for 5-10 min and every smooth out. I was so relieved, thought it was a tow to the shop at this point. I still think the O2 sensor maybe going bad, I have a new one coming this week and I will also change the Protection Relay. If it still acts up, I'll reach out to the experts! Tomorrow after work, I will try to tackle replacing my clutch slave cylinder that's been leaking. Thanks.

 

If possible, do me a favor and curb my curiosity by changing the protection relay first and see if that resolves it before putting in the new O2 sensor.

 

This is what my relay looked like when I open it up.
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Mike: I somehow missed your photos.

From what I can tell the old plugs look ok, don't see any oil fouling or signs of high heat. Do they all look pretty much the same? Doesn't look like there are any carbon tracks in the distributor caps, though the erosion of the rotor and electrodes in the caps suggests those parts have a few miles on them.

I think swapping the relay is a good idea as a test.

Can't say about the 02 sensor, my QV doesn't use one as a feedback mechanism for regulating A/F ratio, but I would think that if yours failed the system would switch to running open loop and use some preset mixture value. OTOH, if the o2 sensor is giving wrong readings this could upset the A/F ratio... sorry, just conjecture here as I don't own a car with a lambda sensor.

I'm wondering if it's maybe related to fuel delivery as well. Somewhere around here I have the official Bosch factory training manuals for K-jet... haven't seen them in awhile, but I'll look tomorrow.

It might be helpful if you can isolate the problem to a cold start phenomenon versus something that also occurs in a fully warmed-up situation. Does this also occur with warm starts?

 

I didn't take my old one apart but mine rattled like a baby toy when I shook it. New one, of course, did not.

 

Hi, its not just a cold start problem from what I have noticed, it idles rough at fresh start in the morning and I also noticed it acting up in an afternoon drive when it was warmed for a while. That's why I think its the O2 sensor but its trial and error for now. It could be my K-Jet going bad if not the relay. Thanks.

 

BTW, where is the Protection Relay located on a 3.2 Mondial, is it in the back trunk area ? I will order one tomorrow.
Thanks.

 

I believe it is in the passenger rear for the mondial 3.2. I would check in the boot under the carpet or an attachment to the chassis in the same area.

 

Yes, the protection relay is in the trunk, passenger side. You must remove the carpet first.

When the car is cold, the computer does not take any lambda o2 readings till after the car is warm. Did you make sure no air was getting in from a hose. In your pics, those hoses look as old as the car, and the T connectors may be rusted. I had to replace my T connectors because they were rusted and unmetered air was leaking in.

 

Thanks PT328 and trendsetterx. I forgot I washed the plug wires with soap and water but dried them, so maybe had some water inside a bit at first start which could explain the stall and really rough running. After a while, it all smoothed out, but I still think its a relay or o2 sensor that is intermittent and going bad. Will order a relay today and try that next as PT 328 suggested.

(trendsetterx) - which hoses were you referring to that looked old, I assume its these and will look at them again for leaks #8 T-union for air injection. Did notice 3 small pin holes at the mid section curve side of the #29 'Pipe from support throttle valve body' but it was not bad to the point of needing a replacement.

Thanks again for the great advice.
-Mike
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Hey Mike, thinking simple and common problems first, any chance it's a bad ignition wire/extender? It also seems as though you didn't replace the distributor rotor or cap when you were in there.

 

Hi Jay,
I have one cracked extender that I accidentally stepped on while it was on the floor, but its still functional and just the shell housing small edge piece broke off, new one ordered already. The others look okay from what I can tell with no signs of wear or burn marks. I did not replace the distrib cap or rotor, they looked fine to me after cleaning them and still have many miles left. I'm thinking its pointing to the relay prob, don't know, but want to start the car after work today and see if its any better. This time I'll try to get video for evidence.

thanks.

 

The 100% sure way to know if you have a problem in the protection relay system is check if the frequency valve is "buzzing", or not, during engine operation:

Symptoms for protection relay system problem (with everything else OK):
cold-running = bad (weak)
warm-running = bad (weak)
frequency valve not buzzing during engine operation

Symptoms for O2 sensor system problem (with everything else OK):
cold-running = good
warm-running = bad
frequency valve is buzzing during engine operation

Good Hunting!

 

Thanks Steve, this is very helpful, sounds more and more like a relay prob, but I thought I heard a buzzing sound, here is a video I took after it smoothed out after 10 min and it sounded okay.
I have a protection relay on order from Pelican parts, a few days for delivery.
[ame]http://www.youtube.com/watch?v=OVsYwGEP7To[/ame]
-Mike


I wish I took a video of the start, it was horrible and stalled a few times with misfiring and all. Will try to start it up again today after work.

 

Got home today, raining outside so didn't take her out for a drive. I started her up, she started on the second try but much better today, no back fire, no rough idling, however it did dip 2x but never stalled then smooth out. My starting problems yesterday could be related to wash water of the ignition cables/distrib cap which has now fully dried up. I had a video of the start but the playback has no sound, so this is the second video like 5 mins after I started the car. I am so relieved she is back to pre-maintenance performance, but will be changing the buzz Relay and O2 sensor, she should be as good as new.

[ame]http://www.youtube.com/watch?v=DYFEAR-WSso[/ame]