s300s4 chips and 24# injectors wont run
#16
Intermediate
Thread Starter
Join Date: Apr 2015
Location: Southern Ontario
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
That's why I want to try swapping the chip back to stock with the bigger injectors. Eliminate one variable at a time. I figure if it runs better (but rich) then the bad chip scenario might be the culprit. If doesn't make a difference then it's likely something else. Worst case there's a problem with the injectors and I just revert back stock and the s300 EZ chip. I was happy with the performance. Just didn't want to waste the money I had spent on the new injectors without giving it a try. I have the car is supposed to run much more smoothly with the full package... Still hoping to get it to work.
#18
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
If the injectors have been sitting for a long time they can stick - not often but does happen.
You may want to get a noid and check they are firing. We test before we ship.
If one is stuck a tap on the side can free them.
You may want to get a noid and check they are firing. We test before we ship.
If one is stuck a tap on the side can free them.
__________________
![](https://cdn.shopify.com/s/files/1/1694/8685/files/928sRus_rennlist.png?v=1621798567)
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
![](https://cdn.shopify.com/s/files/1/1694/8685/files/928sRus_rennlist.png?v=1621798567)
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
#19
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Best Practices for me with old-used injectors is to always test them with some fluid pressure (WD40) to make sure they work before the go on the car.
#20
Inventor
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
My local injector guy doesn't want to clean them unless they are going to be installed within a few days - even after oiling.
I hit each injector with full 12 or 14 volts before installation. Sometimes ones from eBay required a few jolts to get them working.
I hit each injector with full 12 or 14 volts before installation. Sometimes ones from eBay required a few jolts to get them working.
![](https://members.rennlist.com/porken/InjectorTest.jpg)
#21
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
If i can bolt on a 30lb injector and have no issues (vs prior 19psi) i would think that your issues with the 24s is something with the injectors or the chip
sounds like that can be the issue here
#22
Intermediate
Thread Starter
Join Date: Apr 2015
Location: Southern Ontario
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Tried the coding plug. No change. Put the stock chip back in. No change. Next is to put the stock injectors back in. I have something to do this evening so it will be tomorrow before I can do that. Hopefully it all runs well when its back the way it was. Maybe I'll find a place that can check the injectors and try again at a later time. I really would like the whole package.
Next time it will be easier.
P.s. could they have found a more awkward location for the computers.
pps. Wouldn't they get a 12v zap when you crank the engine or is it a much smaller voltage in normal operation?
Next time it will be easier.
P.s. could they have found a more awkward location for the computers.
pps. Wouldn't they get a 12v zap when you crank the engine or is it a much smaller voltage in normal operation?
Last edited by M_E_C; 06-01-2016 at 07:31 PM. Reason: added a note
#23
Inventor
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
You might try adjusting the CO thing CCW, too.
#24
Rennlist Member
Join Date: Sep 2010
Location: Fresno, CA (summer in Calgary)
Posts: 1,376
Likes: 0
Received 2 Likes
on
2 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Tried the coding plug. No change. Put the stock chip back in. No change. Next is to put the stock injectors back in. I have something to do this evening so it will be tomorrow before I can do that. Hopefully it all runs well when its back the way it was. Maybe I'll find a place that can check the injectors and try again at a later time. I really would like the whole package.
Next time it will be easier.
P.s. could they have found a more awkward location for the computers.
pps. Wouldn't they get a 12v zap when you crank the engine or is it a much smaller voltage in normal operation?
Next time it will be easier.
P.s. could they have found a more awkward location for the computers.
pps. Wouldn't they get a 12v zap when you crank the engine or is it a much smaller voltage in normal operation?
#26
Rennlist Member
Join Date: Sep 2010
Location: Fresno, CA (summer in Calgary)
Posts: 1,376
Likes: 0
Received 2 Likes
on
2 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
When this happened to my car, an initial fix was to simply disconnect and reconnect the MAF. For some reason this jolted it back into performing sort of correctly, although it was still rich. It ran OK for several months until it finally gave out completely.
#27
Rennlist Member
Join Date: Sep 2010
Location: Fresno, CA (summer in Calgary)
Posts: 1,376
Likes: 0
Received 2 Likes
on
2 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Let's discuss this for general info: is it even theoretically possible for a bad LH chip to kill the MAF? I thought the MAF was a sensor sending signals to the LH, not the other way around. Is there two-way communication that would give the possibility for that kind of destruction?
#28
Intermediate
Thread Starter
Join Date: Apr 2015
Location: Southern Ontario
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I took out the 24# injectors out. I checked them by zapping with 12v. Only 2 of the eight could be made to click when voltage was applied. No amount of tapping and zapping would make those 6 fire. So I checked the originals. They all fired fine. So I reinstalled them. Before firing it up I figured I would check the oil. I mean with all the evidence of extreme rich running I thought some fuel may have washed down the cylinder walls. Yes. The oil is badly contaminated. So I guess next I will drain the oil fill it and flush with some inexpensive oil before refilling with some mobil1.
Any advice on this?
Thanks
Any advice on this?
Thanks
#30
Intermediate
Thread Starter
Join Date: Apr 2015
Location: Southern Ontario
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
There a brown color to it which I would think indicates some water contamination too. the oil smells of gas though. If it is water I don't know where that would come from. what oil contaminated with gas look like?