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Hard start issue

Old 12-23-17, 08:58 PM
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Hard start issue

Hello, I have recently rebuilt my 13b and converted to a single turbonetics turbo. Also took off all the emissions related things. Car has a apexi power fc and data log it. Factory injectors and bridge ported.
on to the starting issue. It is very hard to start. If you give the car full throttle and let off it tries to fire and spins faster, every once in a while it will catch and run. If I didn' explain anything properly, let me know, I have been fighting this for 2 months and I'm out of ideas.
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Old 12-24-17, 08:01 AM
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When rotaries are rebuilt, the first 300 km or so, the compression is low, after 3-500 break in km the engine should be easier to start, as compression gets better.
i use a bit of 2 stroke oil in the uim to help with compression, when starting fresh engines.
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Old 12-24-17, 11:55 AM
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Originally Posted by Auning View Post
When rotaries are rebuilt, the first 300 km or so, the compression is low, after 3-500 break in km the engine should be easier to start, as compression gets better.
i use a bit of 2 stroke oil in the uim to help with compression, when starting fresh engines.
do you pull the uim off and pit a little oil in each runner, or is there a better way.
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Old 12-25-17, 10:22 PM
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Why are you giving it full throttle when starting and then letting off? If that is what you are doing, then it is wrong. Full throttle while cranking cuts off the injectors.
A new engine is tight. Only thing is to set the idle speeds higher than normal due to the large ports.

Attached the map in zipped format with list of all non stock mods. This should be on the PFC forum.
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Old 12-25-17, 10:30 PM
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Originally Posted by cewrx7r1 View Post
Why are you giving it full throttle when starting and then letting off? If that is what you are doing, then it is wrong. Full throttle while cranking cuts off the injectors.
A new engine is tight. Only thing is to set the idle speeds higher than normal due to the large ports.

Attached the map in zipped format with list of all non stock mods. This should be on the PFC forum.
because the engine tries to fire about mid throttle. Also of i dont give it any throttle it will never try to start. And if I could get it to run I would set the idle. but I can't.
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Old 12-26-17, 06:43 AM
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On the rew there are 2 conections for vacume lines were the uim mates to the lim. Its on the uim.
i use a funnel and å vacume hose to get a bit of oil in to each rotor, then i crank it.
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Old 12-26-17, 11:40 AM
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You shouldn't have to do that if the motor was built right and the starting enrichments on the tune are set correctly. Using oil is just covering up an issue.
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Old 12-26-17, 12:03 PM
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Do you have a video? Alot of times the oem wiring/fuse box sucks and drops voltage to starter. I've had difficulty starting new engines in past until replacing battery wiring directly to starter for maximum amperage, least amount of voltage drop. Is your battery relocated? Can you see cranking rpm somehow ?
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Old 12-26-17, 12:04 PM
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It also helps to fire the engine off on starter fluid. Spray a few shots into intake elbow, with injector relay/fuel pump disabled, only ignition/coils on. This gets it coughing easily without flooding
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Old 12-26-17, 06:13 PM
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Originally Posted by Monsterbox View Post
It also helps to fire the engine off on starter fluid. Spray a few shots into intake elbow, with injector relay/fuel pump disabled, only ignition/coils on. This gets it coughing easily without flooding
Update, finally got it fired up, had to perform a deflood procedure and put the factory ecu back in,

Does anyone have the information from their
Power FC tune for a bridgeport, with a 67mm single turbo and stock injectors, just something to get me started with the apexi unit. I'e tried re initializing the unit but had the same issue, no start/ flooded,
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Old 12-26-17, 09:09 PM
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Originally Posted by Jeremyv2892 View Post
Update, finally got it fired up, had to perform a deflood procedure and put the factory ecu back in,

Does anyone have the information from their
Power FC tune for a bridgeport, with a 67mm single turbo and stock injectors, just something to get me started with the apexi unit. I'e tried re initializing the unit but had the same issue, no start/ flooded,

What part of alabama are you in?

You could just start by pulling fuel out of the map at idle cells, make a big correction like -25%, try to crank it up, see if it stays running, if it fires up, see if it sputtters out and stalls from going lean, then add back in a little more until it stays alive. If floods again, repeat with even less fuel, no?
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Old 12-26-17, 09:36 PM
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Originally Posted by Monsterbox View Post
It also helps to fire the engine off on starter fluid. Spray a few shots into intake elbow, with injector relay/fuel pump disabled, only ignition/coils on. This gets it coughing easily without flooding
Originally Posted by Monsterbox View Post
What part of alabama are you in?

You could just start by pulling fuel out of the map at idle cells, make a big correction like -25%, try to crank it up, see if it stays running, if it fires up, see if it sputtters out and stalls from going lean, then add back in a little more until it stays alive. If floods again, repeat with even less fuel, no?
9

I live in guin alabama.
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Old 01-01-18, 08:13 PM
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Ok I have it where it will start every time from a cold start, but when the Pfc indicates anything over 20c, you can forget about it ever starting. If you let the temp drop back down it will crank easily. I would be in good shape if it wasn't for this issue.anyone have an idea?

Last edited by Jeremyv2892; 01-01-18 at 11:22 PM.
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Old 01-02-18, 08:37 AM
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Originally Posted by Jeremyv2892 View Post
Ok I have it where it will start every time from a cold start, but when the Pfc indicates anything over 20c, you can forget about it ever starting. If you let the temp drop back down it will crank easily. I would be in good shape if it wasn't for this issue.anyone have an idea?
in a side note I tried to move the car this morning, and It started fine, I let it die out immediately after and It wont start back?
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Old 01-02-18, 11:41 AM
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Just spit-balling here since your original synopsis doesn't necessarily point to this....But try jumping the two biggest wires of the H302 security relay. Will be very simple to eliminate this common electrical gremlin from your issues. #frustrating
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Old 01-02-18, 03:26 PM
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Originally Posted by Topolino View Post
Just spit-balling here since your original synopsis doesn't necessarily point to this....But try jumping the two biggest wires of the H302 security relay. Will be very simple to eliminate this common electrical gremlin from your issues. #frustrating
I probably wasn't very clear explaining. But the starter always spins and turns the engine over, it will fire up and run once, but if it dies out it will not start back up. You can hear it firing off and spin faster and faster, then the engine rpms drop back down. And it keeps repeating. But if you walk away, say 45+ minutes it will start back up. I don' have anything inhibiting the starter operation itself. It' fine.
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Old 01-02-18, 03:37 PM
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what do the lower plugs look like after trying to restart?
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Old 01-02-18, 08:00 PM
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Originally Posted by Howard Coleman CPR View Post
what do the lower plugs look like after trying to restart?
I'll pull them tommorrow and let you know,
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Old 01-02-18, 08:39 PM
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Check compression and for vacuum leaks.

are you logging afrs when it's idling?
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Old 01-02-18, 09:19 PM
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Originally Posted by Fuhnortoner View Post
Check compression and for vacuum leaks.

are you logging afrs when it's idling?
yes I have an innovative wideband hooked into the datalogit. And what should be my expected compression numbers? I checked all my vacuum lines and they are good,

Last edited by Jeremyv2892; 01-02-18 at 09:27 PM.
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Old 01-02-18, 09:41 PM
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Originally Posted by Jeremyv2892 View Post
yes I have an innovative wideband hooked into the datalogit. And what should be my expected compression numbers? I checked all my vacuum lines and they are good,
​​​​​​​So what are your afrs at idle?
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Old 01-03-18, 09:00 AM
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Originally Posted by Fuhnortoner View Post
So what are your afrs at idle?
10.8 to 11 ish. Pretty rich
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Old 01-03-18, 11:58 AM
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A bridge port pulls significantly less vacuum and will therefore put you in a different part of the map during cranking and idle. In most cases you will have to pull fuel out. If you didn't adjust the tune for the port there is a good chance that is why it is so difficult to start. Deletion of the airpump and some other emissions equipment will also affect the tune and need to be compensated for. Finally, with the stock injectors you will run out of fuel very quickly (probably by 7 or 8 lbs with the porting and single turbo). Unless you are just using the stock fuel system for now to start the car, I would strongly recommend upgrading.
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Old 01-03-18, 01:31 PM
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Originally Posted by IRPerformance View Post
A bridge port pulls significantly less vacuum and will therefore put you in a different part of the map during cranking and idle. In most cases you will have to pull fuel out. If you didn't adjust the tune for the port there is a good chance that is why it is so difficult to start. Deletion of the airpump and some other emissions equipment will also affect the tune and need to be compensated for. Finally, with the stock injectors you will run out of fuel very quickly (probably by 7 or 8 lbs with the porting and single turbo). Unless you are just using the stock fuel system for now to start the car, I would strongly recommend upgrading.
I plan on upgrading the secondary injectors and pump after I get it cranking and idling good.

what part of the map would I be in, which cells.
and I really appreciate your help so far.
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Old 01-03-18, 02:22 PM
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Not familiar with PFC, but its either the map under the tabs "Inj Map" or "Base Map". It looks like the column is absolute pressure and the row is RPM. Find out which map it is before you start messing with stuff. I dont want to be responsible for your blown engine.
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