44 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 starting troubles
Leading reported evidence
Replace starter, works great now, better than
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
Ended up replacing the starter, works great now, better than when new.
Leading evidence: 'Replace starter, works great now, better than' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check air pressure' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
You used the electric fan to dictate the engine temp.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
It's like checking air pressure with one gauge and then the other to find out they read differently.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
If you check it more than once while the engine's running, only the first check will require you to wait.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I need to do a search and change my outside temp to water temp, I guess so I can talk "digitally" and not "analogically" (probably not a word, but sounds good).
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I need to do a search and change my outside temp to water temp, I guess so I can talk "digitally" and not "analogically" (probably not a word, but sounds good).
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
But once it warmed up to 180 (185 the electric fans kicked in and the sensor was in the block not the radiator), then it got up and went, probably because I was dumping so much fuel into the system that more heat helped it run better.
Run lower thermsotat temperature than what the manufacturer
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I have seen cars run a lower thermsotat temperature than what the manufacturer used, and the cars lost power because the cars never made it out of warm-up mode.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
44 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
1 acknowledgements have no verified action link; they do not establish a repair result.
I am having trouble re-starting my 1999 996 after it heats up(200), its starts to turn over but it seems like there is almost a hydraulic lock and it wont start. It starts fine cold, and will start fine after cooling down as well. The battery is less than a year old, and the alternator is charging fine.
Has anyone else experienced this? Any help would be appreciated.
Thanks,
Brett
I had a similar problem about 2 years ago. The car won't start (you could hear the starter clicking but the engine won't turn over) once the car got warm. I ended up having to replace the starter.
These two dont go together, trust me, did it twice.
Unfortunately to load test the starter, it would requiring removing it which would be a PITA. You can load test the battery at Autozone for free, it will tell you if a cell has failed.
I don't think Porsche would agree with that. I know some here have strong feelings about whether this is good or not, but the fact is that these cars routinely run at 90 degrees Celcius (194 F) or higher fully warmed up, and in traffic and hot weather, well above 100 (212F), as read from the OBD display.
riad
180 degrees?! Mine levels out over the 180 degree mark (just over). Is that a 1999 thing with the 2 radiators? I thought 180-200 was the norm.
I need to do a search and change my outside temp to water temp, I guess so I can talk "digitally" and not "analogically" (probably not a word, but sounds good).
The Mk 2 cars show cooler operating temps. Some say that cooling system improvements were made, but I don't know what. What I do know is that the coolant temp sensors are different on the two cars. 99-01, there's one sensor at the engine. After that, there were two, the other one I think at the rad. The readout showed an average, so was always lower than typical for the 99-01, notwithstanding other changes.
You can push some buttons on your climate control to get the OBD to give up the real operating temperature. Do a search.
EDIT: Here it is, courtesy of 1999Porsche911
"Press and hold in the recirculate and the top (arrow up) buttons on the right side of the panel for a few seconds. The left screen will change. Using the + key below that screen, advance so the display reads 6c. Then press the center vent button once. The display will show you your coolant temp.
To go back to normal, simply press AUTO."
Once you've done this, it will default to this mode just by following the first step. If you check it more than once while the engine's running, only the first check will require you to wait. The readout is instant after that.
Forget the temp gauge. It is not even close to being accurate. Your 996 CANNOT run at a coolant temperature of 180F. Even the thermostat is not oipen at that temperature.
Confused. Mine runs above that temperature all the time. At that temperature, it's not even really warmed up (that's just 82 degrees C). Keystroke error, maybe?
The thermostat opens at 183F. Your minimum, fully warmed up engine coolant temp on a stock 996 or 997 is 190F in the best of conditions. Once warmed up, you the coolant temperature willnever fall even close to 180F, regardless of what the gauge says.
Clearer?
Both my 01 and my 04 will settle with the needle between the "8" and the "0" of 180 and rarely if ever go much higher. And keep in mind that I mostly drive in bumper to bumper NYC traffic and it gets hot here.
Never tracked the cars but I would expect the temp to rise on the track.
Like I said above, your gauge is wrong. On the 3.4, you will most always be between 200F and 220 F driving around town in warmer climates. Your engine CANNOT maintain a coolant temperature of 180 even in ZERO degree temps.
When your gauge needle is spltting the "0" in 180, your coolant temp is approximately 215F.
So the 3rd radiator will not cool the operating temperature down, but will only offer a safety factor in the case of extreme conditions? Obviously it can't cool below the thermostat activation point, and I'm sure we (and Porsche) wouldn't want that, If I'm hearing right? If I'm reading this right, Porsche wants these engines to operate between 200-220 degrees?
My understanding is that the third rad is a great mod for the track, but that if your concern is heat buildup at low speeds, the fan mod is a more appropriate solution. I imagine 1999 will comment.
The high temps are purely for reducing emmisions.
Whatever thermostat temp. Porsche has used is where the ECU is going to be most efficient to operate the engine fuel/timing.
I have seen cars run a lower thermsotat temperature than what the manufacturer used, and the cars lost power because the cars never made it out of warm-up mode.
Mostly carbbed cars in general can make more power with a lower temp thermostat.
Actually, the thermostat has nothing to do wth the final temperature of the coolant. You can put in one that opens at 150F and your coolant temps will be no different. The running engine temperature is the result of the high compression of the engine. Unless you increase your coolant flow and/or efficiency of the radiator, you will not get any lower temps. There is nothing you can do that will reduce engine temps to 180F on an 11:1+ engine.
Agree with the first part and I didnt state differently.
I differ the second part. I have been around plenty 12-13:1 engines on the street run at 160 degrees using 160 degree thermostats. This using Autometer gauges which are very accurate. It just takes a large radiator, simple as that. Water volume (relating to the water pump) is almost irrelevant, you can only flow enough water through a thermostat.
There is not an efficient enough radiator that will maintain a high compression engine at 160F. You either remember incorrectly, your gauges were inaccurate or you read the gauges on there way up before the engine reached normal temperature. Laws of physics dictate that to be factual.
Water volume is a VERY important part of the effeciency of the cooling system. To little and you will run hot. Too much and you will run hot. There is no gasoline internal combustion engine on the road today that runs with a coolant temperature as low as 160F without chemical assistance.
1. I am speaking of old muscle cars (carbbed) regarding temps (FI cars will run terrible at low engine temps), and yes, the gauges were accurate (Autometer).
2. A factory pump is usually sufficient for cooling as you can only flow as much as the I.D. of the thermostat permits.
As I stated above. no gasoline internal combustion engine will run as low as 160F, including low compression, carbed engines. Doesn't matter is it's an old 340, 351, 360, 289, 396, 427, 500, 302 or whatever. Even if you could maintain that low an engine temperature, the combustion efficiency would suffer. There is an optimum temperature needed for perfomance and 160F is too low.
Maybe you had the transmission temp gauge confused with the coolant gauge?
But, regardless, the engine's coolant temperture was higher than 160F.
The volume of water through the water pump is determined by 2 things. Pressure and the size of the path. Increasing either will increase volume. The 996 water pumps flow less than required and these pumps were later redesigned by Porsche to allow for more flow.
Ok, why would companies sell a 160 degree thermostat?
Me and my friends bought them by the box full (not literally) for our cars? It was an easy hp gainer for our cars. Yes, some cars would go over, say 165-170, but in general, 160 could be achieved as long as there wasnt stop and go traffic.
Look at Autozone, they sell several brands of 160 thermostats for older cars. They sell them for a reason.
Like I said previously and you agreed to, the thermostat has absolutley nothing to do with the final operating temperture of the engine. All a thermostat does is determine when the coolant will flow to the radiators...nothing more. Remove your thermostat from your car and install a washer that has the same size hole as the thermostat did and your coolant temperature will not be even 1 degree different. The thermostat is designed to maintain a MINIMUM engine temperture and not a maximum and to get to the minimum as fast as possible.
Not to step in or on any toes during your discussion, I just wanted to add my 2 cents.
I would hate my carbed or FI engines to run at 160 degrees, neither would operate correctly. Now cooling the air from a SC is a different story.
In regards to the meters, I love my Autometers on my race Mustang and they are all 'direct' reading gauges, meaning not electrical. For instance the temp gauge is a sending unit hardwired to the gauge, not an electrical sensor with a wire going to the gauge. The oil gauge uses a direct feed line from the engine to the gauge, not a electrical sensor with a wire going to the gauge. I trust the direct reading gauges much more than the electrical reading, but are they really that accurate still? It's like checking air pressure with one gauge and then the other to find out they read differently. Calibration of gauges should be done on a regular basis if you are truly racing at the high-end of your sport (OK any end).
Depends on the situation. A thermostat will control max temp if the radiator can easily maintain a lower temp than the thermostat is rated at.
Gotta go, I brought in old cars into the conversation. I dont care to talk about coolant issues anymore as we beat this horse enough, the 996 is pretty maxed out and limited because of the design.
Thanks Doug,
It does seem like it wants to crank, but doesn't seem like it has enough to turn the engine over a full revolution, almost like there's too much compression if that makes sense.
Brett
FI, I agree 100%, that is by electronic design.
Carbed, ever stomp the throttle on an ice cold V8? Doesn't it always have more power when the engine is cold? If you tune a carbed motor at 160 degrees, it will make more power than if you tuned to 180 degrees. It is simple, cooler, denser air into the engine. That is the whole point of running cooler thermostats in engines from the beginning.
Ahhh, one more beating for the dead horse.
Actually my experience was with a 351C running a tunnel ram with dual holley 600's in a 1970 Maverick. I had a 3-core radiator with a great water pump and a 165 thermostat. But if I punched it without it warming up it was a dog, so I have to disagree with you on that it has more power when the engine is cold, in my situation specifically. But once it warmed up to 180 (185 the electric fans kicked in and the sensor was in the block not the radiator), then it got up and went, probably because I was dumping so much fuel into the system that more heat helped it run better. So again in my case it has to be over 160.
Failing starter seems like a reasonable bet. You can find a Bosch reman starter for under $200 (plus core) and it isn't difficult to replace once you have the intake plumbing out of the way.
Even tho your battery is new, do not assume that it is good. A battery with a dead cell will give you the same problems when warm. I would first eliminate the battery and connections as the cause by swapping batteries with one of your other cars.
Also, do not rule out the ignition switch.
Not knocking the combo but a tunnel ram with 1200 CFM of carbs on a Cleveland? Unless you were revving 8000+ RPMS...............??????????
8 jets, 8 venturis, 8 step up pumps, 4 idle jets, 16 air bleeds, you had a lot on your plate to tune this combo.
I assign this to the weak power at cold temps. The hotter the engine, the LESS FUEL you need, not more.
You used the electric fan to dictate the engine temp. If you turned the fans on sooner, you could possibly of maintained closer to 160.
I hear ya, I miss my 2 '69 Camaros that are long gone. Both were supercharged and wicked also. My coupe could roast the tires in drive at anything under highway speeds.
Hey wait a minute, we are supposed to be having a bowtie vs. blue oval fight.
Had similar problem, once the engine and drivetrain got heat soaked and tried to start the car, as you mention, seemed like the starter was initally bound up then would eventually turn over and start. Initally thought the starter need to shimmed out a bit but was not an option on these. Ended up replacing the starter, works great now, better than when new. Think this was a problem from day one.
