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White Smoke on Cold starts

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Old Aug 8, 2018 | 12:54 AM
  #1  
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White Smoke on Cold starts

Alrighty, so I'm not for sure if this is the right place to post this, and I have searched all over, none apply to my situation. So I just bought a 91 base. It has problems idling and seems to flood everytime I start it after it has sit for a day. It is tough to start and blows out tons of white smoke. The smoke goes away after about 5 minutes. I'm sure its not coolant because it always stays at the same level and I have none going into the overflow tank like on my old fc. I also did a compression check and it has over 110+ on both rotors. My first diagnosis was leaky injectors but I'm not sure. It also has a jumpy idle once it warms up. Sometimes it bounces from 1000-2000. Its not a rough bounce it just goes up and down slowly, and sometimes it just stays at 2000. Please help!!!!
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Old Aug 9, 2018 | 05:31 AM
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The first thing to do for the idle is to check for vacuum leaks and ensure the throttle position sensors are set properly.

As for the white smoke I would pull the plugs after the car has sat to confirm that no coolant is present on them. Also confirm that the plugs are in good condition and that the center electrode is not worn down. It could be that you have some issues ignition causing the flooding and thus the smoking on startup. I would also perform a coolant pressure test and see if there is any drop in pressure during the coolant pressure test. Leaky injectors can cause hard starts so if you do not find coolant on the plugs and the system holds pressure, it would not be a bad idea to send the injectors out to be cleaned and flow tested. This will give you the opportunity to replace the upper intake gaskets as well as any vacuum lines that may have become brittle with age and heat cycling.
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Old Aug 9, 2018 | 12:32 PM
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Check the fuel pressure regulator as well. Does the coolant in the overflow smell like exhaust? Check the PCV system. It’s not an automatic is it?
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Old Aug 9, 2018 | 11:06 PM
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No it is manual. The coolant in the tank does not smell like fuel. However my oil smells like fuel.
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Old Aug 10, 2018 | 05:35 AM
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The oil will at times smell like fuel. Change the oil and filter. I personally use Castrol GTX 20w50. Always have and always will. I only run 10w40 if I intend on driving the car through the fall, just before the snow flies. Either way, keep us updated on what you find out.
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Old Aug 10, 2018 | 11:41 PM
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Well so I checked my coolant today, and sadly it was there was not the same amount as a few days ago. I am going to be renting a coolant system pressure checker to get the final results.
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