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MNBoxster · 09-29-2005, 05:41 AM

Hi,

I think what you're really describing is Hard Starting, that is, the car starts, but only after several attemps am I right?

Hard starting can come from a variety of issues. There just isn't one simple answer here. Hard Starting can often be the result of a combination of issues.

Fuel/Air/Spark - these are the three basic requirements for an engine to run. Let's look at each:

Fuel

a.) Fuel Pump - do you hear it running with the Ignition ON, but before engaging the Starter? Does it sound slow, labored? The Fuel Pump is an electrical device which has fuses and relay(s). The Fuse is most likely good, as the car does eventually start, but the Relay may be sticking sometimes. No good way to easily test a relay, usually swapping it with one known to be good is the best test here.

b.) Fuel Filter - Is it the original? A partially clogged Fuel Filter can make starting the car more difficult as the Fuel Pump is operating just on Battery power until it starts and this can be insufficient for a Pump to work through a clogged or partially clogged Filter.

c.) Clogged or partially clogged injectors can make a car hard to start. There are a number of products out there designed to remove the varnish which your fuel deposits on the injectors. You add these to your Fuel Tank when you fill-up. Try this for a couple tankfuls.

Air

a.) Air Filter, check it to see that it is still servicable and not clogged. Here again, at starter cranking speeds, air is harder to pull through a clogged Air Filter. Remove it and hold it to the light. If visible dirt can be seen, replace it. If a K&N type Filter, replace it with a standard Filter - the K&Ns will clog in 1/3 the time of a standard Filter.

b.) Vacuum Leaks - check all vacuum hoses to make sure they're connected and in good shape. Loose or cracked vacuum hoses will reduce the engine's ability (in some cases) to draw air in, especially at Starter speeds.

c.) MAF Sensor This sensor regulates the amount of fuel injected into the engine by sensing the amount of Air being drawn in. Without an OBD Reader, it's difficult to test it's operation, but if everything else checks out, this could be the culprit. The use of K&N type filters have been known to give the MAF sensors a hard time as the oil in these Filters can contaminate the sensor. If you have one of these Filters, I'd replace it with a standard papper one.

Spark

a.) Battery - The most obvious thing. If it is weak, it is more difficult to start the car. Using a Multimeter, set to DC scale, test the Voltage by touching the Tester Leads to each terminal of the Battery (Car OFF). You want to see a minimum of 12 Volts, 12.5-13.0 Volts would be better. If in doubt, replace the Battery, it may be the Original one and is simply wearing out. Also, check for condition of Battery Cables. Make sure they are not worn, cracked or loose.

b.) Alternator - This is what keeps your Battery fully charged. Check the Accessory Belt (Polyrib Belt) to insure that it is tight enough. Also, with the car running and using the Multitester, check the Alternator's Output as described in my thread about Alternator Testing in the Technical Section here. Correct as necessary.

c.) Spark Plug cables - Inspect these to insure they are not loose or cracked. Replace or tighten as required.

d.) Spark Plugs - Check these to insure that they are in good order, not cracked or fouled. If in doubt, replace them. These are currently on sale at: http://shop.store.yahoo.com/eagleday/993bilovaco.html . Since your car is older, you don't know how long they've been in service, best to replace them and start from a fresh baseline.

If these things do not solve the problem, there are any number of other possible causes which would be impossible to list here.

But, since your car is older, it's probably time to start replacing some of the components I've listed above anyway (unless you have a full Service History indicating that some/all of these things have been addressed) and I suspect that this is most likely to solve your issues. If not, at least you will have eliminated them as possible causes. Hope this helps...

Happy Motoring!... Jim'99

09-29-2005, 05:41 AM	#3
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	Hi, I think what you're really describing is Hard Starting, that is, the car starts, but only after several attemps am I right? Hard starting can come from a variety of issues. There just isn't one simple answer here. Hard Starting can often be the result of a combination of issues. Fuel/Air/Spark - these are the three basic requirements for an engine to run. Let's look at each: Fuel a.) Fuel Pump - do you hear it running with the Ignition ON, but before engaging the Starter? Does it sound slow, labored? The Fuel Pump is an electrical device which has fuses and relay(s). The Fuse is most likely good, as the car does eventually start, but the Relay may be sticking sometimes. No good way to easily test a relay, usually swapping it with one known to be good is the best test here. b.) Fuel Filter - Is it the original? A partially clogged Fuel Filter can make starting the car more difficult as the Fuel Pump is operating just on Battery power until it starts and this can be insufficient for a Pump to work through a clogged or partially clogged Filter. c.) Clogged or partially clogged injectors can make a car hard to start. There are a number of products out there designed to remove the varnish which your fuel deposits on the injectors. You add these to your Fuel Tank when you fill-up. Try this for a couple tankfuls. Air a.) Air Filter, check it to see that it is still servicable and not clogged. Here again, at starter cranking speeds, air is harder to pull through a clogged Air Filter. Remove it and hold it to the light. If visible dirt can be seen, replace it. If a K&N type Filter, replace it with a standard Filter - the K&Ns will clog in 1/3 the time of a standard Filter. b.) Vacuum Leaks - check all vacuum hoses to make sure they're connected and in good shape. Loose or cracked vacuum hoses will reduce the engine's ability (in some cases) to draw air in, especially at Starter speeds. c.) MAF Sensor This sensor regulates the amount of fuel injected into the engine by sensing the amount of Air being drawn in. Without an OBD Reader, it's difficult to test it's operation, but if everything else checks out, this could be the culprit. The use of K&N type filters have been known to give the MAF sensors a hard time as the oil in these Filters can contaminate the sensor. If you have one of these Filters, I'd replace it with a standard papper one. Spark a.) Battery - The most obvious thing. If it is weak, it is more difficult to start the car. Using a Multimeter, set to DC scale, test the Voltage by touching the Tester Leads to each terminal of the Battery (Car OFF). You want to see a minimum of 12 Volts, 12.5-13.0 Volts would be better. If in doubt, replace the Battery, it may be the Original one and is simply wearing out. Also, check for condition of Battery Cables. Make sure they are not worn, cracked or loose. b.) Alternator - This is what keeps your Battery fully charged. Check the Accessory Belt (Polyrib Belt) to insure that it is tight enough. Also, with the car running and using the Multitester, check the Alternator's Output as described in my thread about Alternator Testing in the Technical Section here. Correct as necessary. c.) Spark Plug cables - Inspect these to insure they are not loose or cracked. Replace or tighten as required. d.) Spark Plugs - Check these to insure that they are in good order, not cracked or fouled. If in doubt, replace them. These are currently on sale at: http://shop.store.yahoo.com/eagleday/993bilovaco.html . Since your car is older, you don't know how long they've been in service, best to replace them and start from a fresh baseline. If these things do not solve the problem, there are any number of other possible causes which would be impossible to list here. But, since your car is older, it's probably time to start replacing some of the components I've listed above anyway (unless you have a full Service History indicating that some/all of these things have been addressed) and I suspect that this is most likely to solve your issues. If not, at least you will have eliminated them as possible causes. Hope this helps... Happy Motoring!... Jim'99 Last edited by MNBoxster; 09-29-2005 at 05:44 AM.