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By Christiaan Poortman
Hello, I'm new on this forum and stumbled upon a new problem (or old) with my 2.5l 986 Boxster from 1997.
The problem occurs when the engine is started dead cold after sitting a few hours/overnight.
Engine starts immediately but the RPMs start to surge / hunt between 1100 and 700 RPM. This continues for about 10 seconds after which the idle smoothes out to the normal cold idle RPM.
The first pull away requires a tad more throttle then normal to prevent stalling. After this first pull, everything is almost normal and engine performance becomes better and better. When the engine is hot, the idle sits at 780 RPM with a minor fluctuation now and then (seems to be more than normal)
I've been to two shops (official Porsche dealer and local Porsche specialist). Porsche dealer couldn't find anything and the specialist found the camshaft sensor on the left bank to be unplugged - but now comes the strange thing - the cabling is nowhere to be found!!!!!!? Took the car home to check myself but didn't find anything.
No camshaft related codes to be found in the diagnosis and no CEL either.
Attached one pic showing the sensor and it's missing plug
Could someone help me out? - Is it possible for the engine not to throw a CEL when sensor is disconnected? - where is the sensor wire to be found?
My 1998 Boxster suddenly had hot start issues where if left in the sun here in Texas for a few hours would then crank but not fire unless you kept cranking and pressed the throttle. No issues when starting cold. It had thrown some evap leak codes a few times and a secondary AI once but nothing consistent and would also suffer from idle issues if hot start was hard.
Having read many threads I decided that it was not fuel pressure related as in my experience fuel pumps either work or they do not and the same applies to the associated relay.
I read someone blocked off the valve under the lhs air intake plenum and when I did this the hot start problem disappeared but gave other idle issues.
I decided to replace this valve and in the process also decided to clean the throttle body and iacv when I discovered oil in the aos and j tube the aos was replaced 3 years ago.
Having replaced the valve and the aos the car appears to be running better than ever.
I had no white smoke issues or oil cap pressure test problems and the old valve was in the closed position when I removed it so that may not have been an issue.
This whole situation had gone on for many weeks and also gave air leak codes in both banks but using a smoke generator revealed no issues.
Hi I just bought a cayenne 3.2 V6 2006 base model, on my way home car was running fine,
second day morning went to put some gas and after getting home car idle was rough Stop the engine and start back on now the car start goes to 1000 rpm for 5 seconds and then start shaking going to 500 rpm or less for about 30 seconds then car it self try to correct and goes to 1100 rpm for the same 5 seconds and then back to the bad idle.
If i press de gas pedal right after the start car goes fine without any issue to 4000 rpm for the same 5 seconds and then complete loose the power, back to the 500 Or less rpm. When the car try's to correct back to the 1000rpm I can gas up to the 4000 rpm fine, is like a loop.
I have a Autel Scaner shows 1 code in the getaway
code 532 power supply
what i have done:
new coils and spark plugs
check fuel pump all good
check the spark in the coils
fix 2 vacuum pipes
I have no idea of what else I live in Panama and I'm 600 miles away from the only Porsche dealer. I'm a mecanic but out of ideas now any help will be much appreciated
I have an 996 - 99mod manual 3,4L.
When i start up it seems like it misfires. It`s kind of a knocking sound. Sometimes it stops on idle.
When i push the throttle for a ouple of seconds, it smokes a lot and then the knocking goes away.
After that, I let it Idle - but it slowly rises from 800rpm to around 2000rpm, then it drops to 800rpm again and do the same thing over and over again,
Does anybody have a clue?
This is the fault codes i found:
P1601 -CAN timeout - instrument cluster
P0600 - CAN timeout Tiptronic
P0102 Hot film MAF sensor (erased and didn`t come back)
60 - Central locking limit pos
13 - Left door secured, but not locket
14 - Left door secured, but not locket
16 - Signal from airbag
1 - Doors secures and terminal 15 on
43 - passenger - side release stuck
44 - Driver-side release stuck
61 - Central locking limit position Unlock not reached
By Karl Owen
2007 C4S with Tip and 58,000 miles
My CEL came on yesterday, due to codes 2187/2189. After a brief search on the internet, loose oil/gas caps came up as possible causes. So I cleared the codes and tightened the caps, but the CEL came back a few hours later.
I also just noticed last night that, when idling in Park, it revs at ~1,100. In Drive with the break on and the car not moving (no pressure on the gas pedal) the idle revs drop to normal (around 700-800). Also the idle is a little rough. Any ideas what causes this? Thank you all.