![]() |
|
|
|
Writer/Teacher
|
More on "The Problem"
Ok, the Fuel Filter and Spark Plugs are on the way (should arrive tomorrow or Tuesday). Yesterday I cleaned out the throttle body and cleaned/oiled the K&N filter. It helped a little, but the accelleration problem is still there. The car pulls like hell at about 3200-4500RPM as long as the upshift/downshift drops the revs right in that area. If I accellerate from low RPMs, the car accellerates slowly, and also accellerates (and Revs) slowly after about 4500RPM. If I mash the throttle at 5000RPM, there is NO difference in accelleration or rev climbing than if i was only gradually pushing the throttle.
Do we still think it's the fuel system?
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
Registered
|
Is the stock chip in there for sure? I didn't read the first post, maybe it's electrical.
__________________
1987 Black/Black (sold) 96' Jetta (RIP) 1986 N/A (Sold) 2001 Taurus noooooooooooooo! ![]() 1993 325is |
||
![]() |
|
Writer/Teacher
|
yeah stock DME
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
Registered
Join Date: Dec 2001
Location: Cordova, TN
Posts: 1,222
|
CJ I dont remember the original post to well did anyone suggest the TPS?
__________________
Roger Hall 81 924 N/A Some people are like Slinkies. Not really good for anything, but you still can't help but smile when you see one tumble down the stairs. |
||
![]() |
|
Custom User Title
Join Date: Oct 2002
Location: Miami
Posts: 4,294
|
well, your car should definitely be pulling hard at 5000, that much I know. If you hit the gas at 5000, the response should be the car 'takes'. then as the turbo spools, the thrust should push and push quickly to redline. Hope you work out the problem, and for little $.
|
||
![]() |
|
Writer/Teacher
|
um 944NA, not Turbo. 1983 model.
Yes the TPS was suggested. It seems that the only way to test the TPS is with an ohmeter (sp?), which I don't have. If someone could recommend a way to 1) get to the TPS, or at least the part of the TPS I need to adjust, without removing the throttle body, and 2) tell me how to adjust it, then I would be most appreciative. FYI, here's a list of my approaches to remedying the problem: THROTTLE CABLE: Cable was a little loose on new throttle cam. I adjusted the cable with the screw that connects the cable to the firewall, as well as the small screw underneath the cam. This made the throttle ultimately more responsive, and therefore improving accelleration, but didn't correct my problem THROTTLE BODY: Removed main hose (the big black thingie that connects the body with the MAF), and cleaned the inside of the throttle body with the butterfly valve closed. I made sure that all the vacuum lines were clean by inserting a needle into each one. Throttle body wasn't dirty/clogged to begin with, so difference was not noticable. AIR FILTER: Cleaned and oiled filter. Difference was negligable. FUEL FILTER: Being delivered sometime this week, after which I will replace. SPARK PLUGS: Being delivered sometime this week, after which I will replace. THROTTLE POSITION SWITCH: Nothing attempted yet; not sure what to do... will attempt tomorrow morning if someone can help me figure it out. FUEL PUMP: Nothing attempted yet. FUEL INJECTORS/FUEL RAIL: Nothing attempted yet, other than running injector cleaner. CLUTCH: Nothing attempted yet. DME: Nothing attempted yet. Thanks, all, any info/opinions/ideas you can give would be much appreciated.
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. Last edited by CJFusco; 06-16-2003 at 05:37 AM.. |
||
![]() |
|
![]() |
Registered
Join Date: Dec 2001
Location: Cordova, TN
Posts: 1,222
|
IIRC my vote was for fuel filter replacment. Try it and see what happens. If nothing else its good PM.
Sorry but I have no insight on the TPS procedure.
__________________
Roger Hall 81 924 N/A Some people are like Slinkies. Not really good for anything, but you still can't help but smile when you see one tumble down the stairs. |
||
![]() |
|
Registered
Join Date: Jan 2003
Location: New York
Posts: 891
|
Quote:
http://www.clarks-garage.com/shop-manual/fuel-06.htm
__________________
Tom Early '85 944 |
||
![]() |
|
Custom User Title
Join Date: Oct 2002
Location: Miami
Posts: 4,294
|
Quote:
![]() |
||
![]() |
|
Certified Rennwerker
|
Disconnect the O2 sensor and see what happens also.
__________________
PCA " I've been everywhere, done everything......just can't remember any of it!" ![]() |
||
![]() |
|
Registered
Join Date: Nov 2001
Location: Melbourne, Florida
Posts: 431
|
Does your car still have it's catalytic converter? Does the console area and floor feel really warm when you drive it? If so, maybe your converter is plugged.
Rob
__________________
1986 951 |
||
![]() |
|
Writer/Teacher
|
"Does the console area and floor feel really warm when you drive it? "
YES! Especially during the day, there is constantly HOT air blowing out from under the dash. Any recommendations? I have a spare exhaust set-up... should I swich over to that one and see if it makes a difference?
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
![]() |
Writer/Teacher
|
Also: how difficult would it be to install my spare exhaust system on my car? Is there a way to simply swap out the cat?
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
suck my tail pipe
|
new plugs and wires probablly.... maybe even a cap and rotor, might as well... good luck..
Frank B
__________________
My car is naughty |
||
![]() |
|
Registered
Join Date: Mar 2003
Location: dfw, texas
Posts: 1,137
|
if you replace everything rear of the the manifold back it would just be a matter of trying to loosen super rusty bolts. the cat is unfortunately welded in
__________________
84 944 Non Alcoholic |
||
![]() |
|
Writer/Teacher
|
"new plugs and wires probablly.... maybe even a cap and rotor, might as well... good luck.. "
I doubt it. I just got a set of Jacobs wires about 1 year ago, and the plugs don't look too fouled (just normal wear). I am changing the plugs as soon as they come in (they were backordered). OK here's a list of things I have checked, and the diagnosis: AIR FILTER - Cleaned and re-oiled with K&N kit. FUEL FILTER - replaced with new item. Saw an improvement in response and an elimination of hesitation, but no cure to "the problem." FUEL INJECTORS - ran fuel injector treatment/cleaner. No discernable difference. Injectors/rail are not leaking, hissing, or bubbling. FUEL PUMP - nothing done yet DME -nothing done yet SPARK PLUGS - going to be replaced with new items SPARK PLUG WIRES - wires aren't that old (1 year max) DISTRIBUTOR - nothing done yet ROTOR - nothing done yet CLUTCH - needs to be replaced, has needed to be replaced since I bought the damn car. Clutch is not slipping, only makes 'whining' noise on decelleration and doesn't quite 'grab' like it used to. EXHAUST/CAT - nothing done yet THROTTLE WIRE/CAM - tightened wire so that cam/TPS clicks as soon as the throttle is touched. THROTTLE POSITION SWITCH - tested with an ohmeter. functioning properly. THROTTLE BODY - cleaned out. spotless. --- perhaps I should get a new distributor and see where that goes? Or maybe I should just wait until i get my clutch replaced under the assumption that the clutch is the problem?
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
Registered
Join Date: Nov 2001
Location: Melbourne, Florida
Posts: 431
|
Quote:
The constast hot air blowing is a completely different problem. Possibly a bad heater valve. Do the early models have the notorious heater clips like the late models? Quote:
Rob
__________________
1986 951 Last edited by robm-951; 06-21-2003 at 05:54 AM.. |
||
![]() |
|
Registered
Join Date: Dec 2001
Location: Cordova, TN
Posts: 1,222
|
Quote:
Have you had the CO level checked? I am not sure about the 944 but in addition to the TPS I would check any sesnors on the fuel injection and airflow. Also I remember some posts about the air intake having a flap that could get stuck or not function properly. The cat could be replaced with a test pipe. However emmisions testing would be a problem if its required in your area. Sometmes when a cat gets cloged it will glow red hot. Run the car hard for about 30 mins then look underneath if the cat is glowing then its definatley cloged. I have never worked on a 944 so I am just guessing but it does sound like a fuel mixture issue not a bad cat. I also would not buy a new distributor unless you have the old is bad. Throwing parts at the car gets expensive and frustrating.
__________________
Roger Hall 81 924 N/A Some people are like Slinkies. Not really good for anything, but you still can't help but smile when you see one tumble down the stairs. |
||
![]() |
|
Certified Rennwerker
|
Yes...Rich/lean adjustment may be needed. These cars with high mileage need readjusted at the MAF to reset the correct mixture. Over time and miles the DME is still set at new mixture. There is a cap on the MAF, drill and tap the plug and remove it with a screw-thats what the tap is for. There is an air mixture adjustment screw under the plug. You will need to have the O2 measured at the exhaust, most shops will be able to do this and get a reading of rich/lean and adjust accordingly. This will get the air mix closer to what the worn motor needs now and will run a bit better! The DME can only read the mixture not adjust it if too lean or rich. Sman
__________________
PCA " I've been everywhere, done everything......just can't remember any of it!" ![]() |
||
![]() |
|
Writer/Teacher
|
924Sman - could you go through the MAF procedure again in detail? i am not as mechanically-versed as many on the board, and therefore need more help finding the right things and a lot of detail in checking/fixing them...
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|