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Another fd that wonít start

Old 07-10-19, 06:04 PM
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Another fd that wonít start

Iím new here so I apologize if this is in the wrong section or something of that sort but I am officially stumped on getting my fd running. It hasnít run in 4 years and I have replaced the fuel pump and rewired it, put new fuel in it, I have changed the oil and filter, I have tried the ATF trick with mmo and have tried deflooding with every method I could find on here with no luck. I have even done a compression check, which showed ~100 psi in both rotors. The car cranks and gives a few backfires but never starts. A faint white smoke can be seen coming out of the tail pipe after cranking. The mods on the car, to my knowledge, are sequential turbos, Apexi ecu and controller, intakes, downpipe and exhaust. If anyone has any ideas or thoughts please let me know.
Thank you,
Eric
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Old 07-10-19, 07:37 PM
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Youíve got compression. If youíre confident itís getting fuel (apparently you are if you certain it flooded) Iíd move to checking spark. If Spark isnít there or weak, bench testing the coils is easy to do with a multimeter. Itís explained in the factory service manual. And a copy of that is free in a download from the FAQ sticky. Also visibly check the wiring to the crank angle sensors and try new plugs.
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Old 07-11-19, 09:02 AM
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If it backfires, that generally means it's getting fuel and spark, but at the wrong time. Check the CAS. Understand the MAP sensor can cause rough running. Check that that's connected correctly (some people erroneously replace the MAP filter with a check valve)

You also said you tried deflooding. Is it flooding? If so, you need to fix that, esp if it's from a leaky injector vs just cranking.

Also, an easy way to check for spark is to ground the plug and turn it over.

If the car is close to stock, except for the ECU, you can try putting in a stock ECU and see if it's throwing any codes.

Good luck
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Old 07-11-19, 12:15 PM
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Thank you for the responses. I have checked the wiring going to the CAS and it all appears to be in order. I will be testing coils and throwing in some other spark plus to see if that a difference. The map sensor has the correct filter and lines going to it so I am assuming that is not the problem. I will see if anyone local has a stock ecu I could get my hands on to give that a try.

I tried starting it with the map sensor unplugged and it made no difference to the engines behavior. Is that a sign of a bad map sensor

Last edited by losing_rx7; 07-11-19 at 12:44 PM. Reason: adding a test
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Old 07-12-19, 03:54 AM
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Your map sensor is likely fine.
You know... I'm not sure what it is with a car that's sat along, and I'm not just talking about rotaries. But over the years I've found that sometimes a starter just isn't quite enough. When all else fails, I'll make sure it's got plenty of oil and the coolant is full and use a truck with a tow-strap. If it starts I'll let it get to operating temp and run it at various speeds for a long time...maybe with some good fuel system cleaner in the tank. Often it'll start fine after that.

Last edited by Sgtblue; 07-12-19 at 03:58 AM.
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Old 07-13-19, 03:08 PM
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I finally got her running today; I threw in some old platinum plugs I had and she fired right up. She idles a bit high but that can be sorted out. Thank all for the input and advice

-Eric
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