20 Most Recent 1990 Porsche 944 Questions & Answers

There is a flat filter that sits between the firewall and the blower. Sometimes the filter is blocked and needs to be cleaned or changed. On older cars the filter is located on the firewall in the engine compartment infront of the blower. In the newer cars the filter is under the dash inside the car and much harder to get too.,

The top on my '91 S2 cabriolet also wouldn't open when i bought it about three years ago. the electrician tested the motor and it was working with direct power. turned out it was the relay that prevents the top from retracting when the car is running. We didn't find where the relay was located but we ran a bypass and added a secondary relay to the bypass located behind the tray under the radio. now ist good as new as new. before u do that though,m try lifting the top's lip while pressing the switching, that can keep the motor from starting as well. good luck.

Is your fan motor blowing? It could be that the fan has stopped working and you're only getting airflow from the forced air coming through the vents. Set the heater to "recirculate" and see if still get air when you're moving. If not, then your fan isn't working. COuld be a bad fan or a blown fuse. Check the fuse first.

My roof just stopped working this morning. My owners manual says that on the left rear side, in the trunk, when you pull back the carpeting there is a place for a crank. You use the spark plug wrench that came with the tool kit, although it is not with my car.

If it's twisted, it has to be replaced. It can't be fixed.

The gauge is faulty,Get a new gauge to replace it

using chevron gas in the tank may be the easiest solution to your problem, don't ask me why but, it worked for me AND I WAS TOLD JUST AS YOU ARE BY ME.

Possibly the signal to the fuel pump. It might be a bad connection where the wires connect to the fuses or the contacts the fuses or relays plug into themselves. Whether the hose is the problem with the starting or not you need to repair it so that the heat will shut off. If there is some way to connect the hose to the broken reservoir or hold it there to verify that the problem goes away first before buying a new reservoir, then I would suggest that.

check the connections at the oil pressure sending unit.

This is not a known solution, but in general these cars suffer from voltage and current drops on electrical connections due to corrosion on contact surfaces. I cannot remember the number of times I have read about electrical problems on these cars, and the problem was usually solved by cleaning the electrical contacts or replacing a relay going bad (BTW, this car does use a lot of relays however I doubt there is one in the fuel gauge circuit).

Also, I have a spare gauge cluster for the 944 and when I look at it, there are some resistors on the "printed circuit" piece. If one of those were to lose tolerance, or burn open, it would no doubt have an effect on the accuracy of the circuit. I would check out that circuitry and test the resistor values as a last resort -- it is not likely the gauge itself if it is working at all. However, before doing that I would clean the electrical contacts thoroughly. I have not tried to gain access to the wiring harnesses for the gauge cluster while it is in the car, but I doubt it is possible. So, if you have exhausted all other ideas go to the Clark's Garage site for instructions on how to remove the dash, and just follow the portion that applies to removing the gauge cluster. Go to the local electronics hobbyist store, or online, and obtain a good contact cleaner and clean all of the electrical contacts while also looking for loose or broken wires. NOTE: Be careful and gentle dealing with the plastic connectors on these cars as they tend to be brittle and little tabs break off easily if man-handled. Go slow, be in the right frame of mind and use good lighting so that you can see what you are doing.

Commonly it's a problem with water in the distributor or coil packs. Which ever you have. 91 probably a distributor.

When you put in airbags, you need to put new airbag sensors as well. If you leave the old sensors in, your airbags MIGHT deploy again. When you change both airbags and both sensors, the system resets itself. I have done this operation before.

Very common problem. Heater control clips break and must be replaced. I found a lot of info on the web including instructions and pictures. Clips are cheap at www.944online.com. They aldo have the instructions and pics.
Good luck

check relays, specially for the starter
check spark plugs
check also your car's electrical grounding connected to the engine area. reconnect it if possible

http://www.pelicanparts.com/944/electrical/944_electrical_diagrams.htm

replace your solenoid, usually that is the cause of wiper issues.

I would take a hair dryer and start to blow dry the coil, all the electrical wires that are attached to the ignition system, is a 12v tester to check primary circuit ( clip the coil + and touch the ground to see if you have elec flow, touch the frame of the car ) if it lit up then I would take the coil to have your mechanic check out if the coil is ok. Then get one of those spark plug wire ignition tester, it just clip on to the ignition wire and turn the motor, just test all 4 wire just to make sure, then the last thing to check is spark plugs, u can remove them but have them rest touching the engine block, turn it over n u shud get sparks going, o/w is the plugs, just replaced them is only like 10-12 bucks each.

I would check all ground connections, clean and refit. then look for additional connectors that split off the tail/runner lights. they are a common circuit for both left and right sides. ty