86.5 928 stalls at 2000 rpm one time after starting. Idle, while smooth, slowly increases from 650 to around 1100

5

Asked by Mar 31, 2016 at 10:20 PM about the 1986 Porsche 928 S Hatchback

Question type: Maintenance & Repair

my 86.5 has an S4 intake installed by the PO that I recently refurbished (see
pic). Also upgraded injectors to Bosch Gen III 4 hole. Also purchased and
installed a refurbished MAF (JD Porsche).  Smoke tested it and seemed fine.
Runs spectacularly except for the initial stall at 2000 rpm and the slow
inexorable increase in idle speed. Idle is also very smooth -- just fast...
Thoughts?

3 Answers

5

Got you all stumped too, apparently... Bummer...

23,485

Well in the pic it looks like a vacume hose is hanging over the valve cover. But my first thoughts would be IAC idle air control. Had similar symtoms with a first gen miata. Im not familiar with 928 as much as i would like to be, so maybe check the 928 forums and see if someone else has had the same issues. Good luck.

5

Thanks for the response. The intake refurb was still in process when the pic was taken so stuff is still disconnected. My leaning is also toward the IAC but on a 928 it's under the intake - -NOT a trivial task!

Your Answer

Add photo

Related Questions

928

Looking for a Used 928 in your area?

CarGurus has 33 nationwide 928 listings and the tools to find you a great deal.

ZIP:

Search Porsche 928 Questions

Porsche 928 Experts

#1 Tom Demyan
Tom Demyan
Reputation 130
#2 MTA1968
MTA1968
Reputation 110
#3 Michael Griffin
Michael Griffin
Reputation 100
View All

Related Models For Sale

Used Porsche 911
119 Great Deals out of 4,601 listings starting at $8,901
Used Porsche 944
97 listings starting at $3,900
Used Porsche 924
15 listings
Used Chevrolet Corvette
202 Great Deals out of 20,888 listings starting at $4,993
Used Ford Mustang
396 Great Deals out of 44,403 listings starting at $1,000
Used BMW 3 Series
1,461 Great Deals out of 38,438 listings starting at $1,700

Used Cars For Sale