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Turbo tC Backfire when starting.

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Old 05-17-2012, 02:43 AM
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Default Turbo tC Backfire when starting.

I have a Turbo Toyotas simple kit with AEM fic, and 700cc DW injectors. I am on a custom base map(afrs are 11 under boost, alot of timing pulled up top). When I try to start the car it will backfire when I am trying and the boost gauge will jump up. It only does this sometimes. What can I do to fix this issue besides a pro tune?
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Old 05-17-2012, 03:10 AM
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this is normal with the FIC i have yet to see a unit not backfire during startups its usually only when the cars been driven already and you go to restart it withing a few hours, sometimes some FIC's make big backfire, others make a small lil pop
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Old 05-17-2012, 04:07 PM
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It was a little pop. Exactly as stated. The other thing is it did it this morning and I had not drove it in 10 hours.
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Old 05-17-2012, 04:13 PM
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Try playing with the fuel map around 14psia and 0-700 rpm. I don't commonly see this kind of issue without a ton of fuel being dumped at start up
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Old 05-17-2012, 04:18 PM
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Also make sure you are not pulling timing till after 14psia. After you have made some slight adjustments to your fuel map if problem persists clear the ecu memory
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Old 05-18-2012, 02:56 AM
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I am pulling 0.75* at 15psia, nothing before then. I can try removing some fuel tomorrow. When you say clear the ecu memory just reset the factory ecu, or is there something special to do on the FIC?
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Old 05-18-2012, 05:26 PM
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I mean disconnect the battery for a min or two.
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Old 05-18-2012, 09:38 PM
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Ok Thanks Crush! When I get my new oil drain line, I will do that.
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Old 07-26-2012, 12:34 AM
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Ok I know posted this thread a while back but here is whats been happening. The car will only backfire after it has been running and warmed up(this happens about 70% of the time). If the car is being cold started it will start right up. I drove about 30 minutes to meet my wife today. I came out started the car and the backfire blew a hose on the IM off. Any ideas on what this is? Maybe I should go to one step colder plugs? The other issue is the car starts up first try when it is cold. When it is warmed up I have had it take as many as 6 times to try to start.
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Old 07-26-2012, 03:18 PM
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Originally Posted by headlessmunky
Ok I know posted this thread a while back but here is whats been happening. The car will only backfire after it has been running and warmed up(this happens about 70% of the time). If the car is being cold started it will start right up. I drove about 30 minutes to meet my wife today. I came out started the car and the backfire blew a hose on the IM off. Any ideas on what this is? Maybe I should go to one step colder plugs? The other issue is the car starts up first try when it is cold. When it is warmed up I have had it take as many as 6 times to try to start.
Let me guess....2007-2010 tC

NM.....Saw your sig. You have an 08.

Do a compression test and report findings.
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Old 07-26-2012, 07:07 PM
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Can I rent a compression tester from an auto parts store? Does it sound like the tune or something worse?
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Old 07-26-2012, 08:20 PM
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there cheap like 20 bucks
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Old 07-26-2012, 08:26 PM
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I found that out lol going to get one tom.

Paul:
Whats the deal with the 07-10s?
What does the problem sound like?
Is this a tune or more serious?

I am kind of worried now!
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Old 07-27-2012, 01:31 PM
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Originally Posted by headlessmunky
I found that out lol going to get one tom.

Paul:
Whats the deal with the 07-10s?
What does the problem sound like?
Is this a tune or more serious?

I am kind of worried now!
Do the compression test and report findings, then I will explain.
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Old 07-27-2012, 02:36 PM
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I will when i get home. i am in hell err the DMV trying to get my tags rebewed. I will pick up a tester and test when i leave. Does the motor need to be cool or warm?
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Old 07-27-2012, 05:13 PM
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Alright Readings are in. I did three test on each cylinder to ensure accuracy. The guage was acting stupid and got stuck in cylinder number 1.

1. 120,130,130
2. 120,122,120
3. 125,125~,125~
4. 130,130,130

They are all low, but consistent(within 10%). The engine has 69k and has had all oil changes every 5k with synthetic oil so I am puzzled.
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Old 07-27-2012, 05:47 PM
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Originally Posted by headlessmunky
Alright Readings are in. I did three test on each cylinder to ensure accuracy. The guage was acting stupid and got stuck in cylinder number 1.

1. 120,130,130
2. 120,122,120
3. 125,125~,125~
4. 130,130,130

They are all low, but consistent(within 10%). The engine has 69k and has had all oil changes every 5k with synthetic oil so I am puzzled.
Are you getting lots of random misfire codes?

Turbocharged, correct? NM you OP says it has a TT simple kit.
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Old 07-27-2012, 05:55 PM
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What's occurring is........On a 2007+ block there are oil squirters present. So when a decent amount of blow by occurs past the rings, soon as you begin cranking this diminishes the octane value of the gas used and causes a violent back fire to occur because that smidgen of oil mixes with the combustion.

Let me also guess that sometimes it blows off your PCV hose from head to intake manifold?

Remove that hose and see if oil is present there.

Remove upper IC pipe and see if oil is present there as well.

Chances are you will find traces of it in all places. Welcome to 2007+ premature engine failure due to lack of tuning.
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Old 07-27-2012, 05:57 PM
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Nope no missfire codes. Just a catalytic converter code(lulz). I watched the gauge go from like 60(turned over once) to 120(turned over twice) then it just kind of bounced in place and moved up just a bit for the other 3 cranks, it also made a squeeking sound. Maybe it is sticking? Maybe I am in denial but I want a solid answer I am going to go buy one later rather than renting one, just waiting on the wife to get home.
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Old 07-27-2012, 06:00 PM
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Originally Posted by headlessmunky
Nope no missfire codes. Just a catalytic converter code(lulz). I watched the gauge go from like 60(turned over once) to 120(turned over twice) then it just kind of bounced in place and moved up just a bit for the other 3 cranks, it also made a squeeking sound. Maybe it is sticking? Maybe I am in denial but I want a solid answer I am going to go buy one later rather than renting one, just waiting on the wife to get home.
The more aggressive engine failure (cylinder pressure of 100 or less) you will see these all the time.
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