Fuel Pump or Wiring?
10-11-09, 12:32 PM
#27
Shinji
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that was an advocated modification notion, but you said, "I went ahead with the de-flood and ATF route, cleaned the plugs and still no go," did the car at least smoke? or even a loud 'click?' did you take all plugs out and spin the motor - crank ignition & gas pedal? let that sit for a long while. inject small amounts of 2 cycle oil into the leading lower chambers and replace with new plugs..check that out. honestly, i think its the wiring, regardless. others include checking your compression. maybe you have leaky injectors. i have lots more opinions on this matter. i hope you get it going.
10-12-09, 09:05 AM
#28
that was an advocated modification notion, but you said, "I went ahead with the de-flood and ATF route, cleaned the plugs and still no go," did the car at least smoke? or even a loud 'click?' did you take all plugs out and spin the motor - crank ignition & gas pedal? let that sit for a long while. inject small amounts of 2 cycle oil into the leading lower chambers and replace with new plugs..check that out. honestly, i think its the wiring, regardless. others include checking your compression. maybe you have leaky injectors. i have lots more opinions on this matter. i hope you get it going.
10-12-09, 03:12 PM
#30
Get new plugs and make sure the battery is charged or has a booster on it. When you pulled the plugs were they soaked with fuel? Its most likely flooded. You can rewire your pump to put out 12 volts but even with 6v and 30 psi it should be enough to start the car. Your sure u have spark at all plugs?
10-12-09, 03:25 PM
#31
I have brand new plugs and yes all plugs are sparking. I can double check that again...Yes the plugs have fuel on them. The battery has a charger on it as well. I even tried jumping the system with my truck...to give it more voltage...but still nothing...I am going to go through the wiring again, I guess and check out the FP resistor and the wiring under the drivers side wheel well. I also am thinking about plugging in the stock ecm to see what happens....I just dont udnerstand it, as the car ran for 5 mins and then since then it never started.
10-12-09, 04:00 PM
#32
Once they are flooded it can be hard to get them running again. Even new plugs can be fuel fouled. Keep going through the deflood proceedure. Make sure you pull the egi and plugs so you can get the fuel out of the chamber. Then put some atf to build compression. New plugs and give it a go. Pull start it if you have to.
10-12-09, 04:16 PM
#33
i usually take them out and burn the ends with a torch to make sure there completely dry and all of the residue/fuel is removed. I have done the de-flood method, usually it will work right away. I honestly dont think its the plugs, becasue there is spark atleast on the leading plug. I will check the others tonight...
10-12-09, 04:40 PM
#34
What kind of plugs are you running? Usually spark output isn't a huge deal on getting a rotary started. But since you have fuel, (wet plugs) I assume you have compression, and lastly spark, thats all that's needed for the engine to run.
Now if the spark isn't hot enough to ignite the mixture....due to atf fluid, (to help build compression) and too much fuel in the chamber, then the car won't start.
The twin power does help a lot in this case. But check each plug for spark, and make sure it's sparking from the electrode tip, to the ground strap. When I had a flooding issue, I personally checked about 16 plugs I had laying around and found all but 5 or 6 that were either not firing or firing against the wall surrounding the ceramic and not at the tip. I also used a torch to burn off the fuel. Anyways. once I had all 4 plugs firing properly I was able to start the car and sort out my flooding issue. Your problem may be something else, but I can attest to the fact that a flooded rotary can be a PITA, and plugs that aren't firing/firing improperly won't help the matter.
Now if the spark isn't hot enough to ignite the mixture....due to atf fluid, (to help build compression) and too much fuel in the chamber, then the car won't start.
The twin power does help a lot in this case. But check each plug for spark, and make sure it's sparking from the electrode tip, to the ground strap. When I had a flooding issue, I personally checked about 16 plugs I had laying around and found all but 5 or 6 that were either not firing or firing against the wall surrounding the ceramic and not at the tip. I also used a torch to burn off the fuel. Anyways. once I had all 4 plugs firing properly I was able to start the car and sort out my flooding issue. Your problem may be something else, but I can attest to the fact that a flooded rotary can be a PITA, and plugs that aren't firing/firing improperly won't help the matter.
10-12-09, 05:02 PM
#36
The stock plugs are one of the worst designs in getting a flooded rotary to fire. I recommend you get some B9EGV's or you can try some BR9EIX's. The EGV's are non resistor plugs, and they are supposedly not to be used with the twin power. I ran them fine for awhile and theoretically they should have a hotter spark from lower resistance.
After you get the car running you can switch them out to something different if you're worried about the twinpower. On a properly running car with an ignition amp I suggest going with 10's not 9's. The 9's retain too much heat and cause the electrodes to burn up prematurely.
The best plugs I've run by far are the greddy race plugs (rebadged NGK R7420's) they are expensive but should save you money in the long run due to lasting so long.
While many people have made gobs of power on stock plugs, the design is terrible and there are much better alternatives available.
Also I edited my previous post and you might not have seen that.
After you get the car running you can switch them out to something different if you're worried about the twinpower. On a properly running car with an ignition amp I suggest going with 10's not 9's. The 9's retain too much heat and cause the electrodes to burn up prematurely.
The best plugs I've run by far are the greddy race plugs (rebadged NGK R7420's) they are expensive but should save you money in the long run due to lasting so long.
While many people have made gobs of power on stock plugs, the design is terrible and there are much better alternatives available.
Also I edited my previous post and you might not have seen that.
10-12-09, 06:11 PM
#37
Thanks for the advice. So I just got home and figured I would do a visual inspection on the drivers side fender to see if the wiring loom had indeed grounded itself. But visual inspection everything looks great. Now gets to some interesting matters. I tested both egi and circuit relays and they click when you add 12v to them. So I figured I would swap to the stock ecu and same thing nothing. MY fuel pressure is at zero when i put both relays back in. but i tried to jump the diagnostic connector with both relays in and I get no pressure from the pump or any voltage...But if i jump the circuit relay i get about 30psi of pressure....
Now I checked the fuel pump resistor under the cruise control for continutity and I recieved 2.4 ohms....thats alot higher then what the FSM stated ( .57- .70 ohms) Wondering if that has something to do with with my 6.5 volts to the pump when i jump the circuit relay...
I am unsure what to do next....When I jump the pump directly to the battery I get 12V but the car doesn't start....did before but now it won't.....wierd this thing is killing me!!!
Now I checked the fuel pump resistor under the cruise control for continutity and I recieved 2.4 ohms....thats alot higher then what the FSM stated ( .57- .70 ohms) Wondering if that has something to do with with my 6.5 volts to the pump when i jump the circuit relay...
I am unsure what to do next....When I jump the pump directly to the battery I get 12V but the car doesn't start....did before but now it won't.....wierd this thing is killing me!!!
10-14-09, 12:07 PM
#39
As I stated already that is not why the car isn't starting. You know this because you jumpered the F/P and it still wont start. You're getting fuel to the rails, thats all that you need. Hell I could stick a rag with gas over the throttle body and get my car to start, you don't need much. But you can bypass the resistor and fix that problem now, you don't want to be boosting the car if the pump is only getting 6 volts. There are plenty of fuel pump rewire writeup's on this forum. Heres the one I personally prefer. 
Did you check for spark at ALL the plugs? Did you check that ALL your plugs are firing properly? I got a little lost with your previous statement of testing EGI and it worked and didnt work at the same time, and that your fuel pump doesn't come on at all unless the circuit is jumped. Is this something new thats happening? Cause last I remember you were getting 30 psi and I don't think you had to jump the circuit?
Did you check for spark at ALL the plugs? Did you check that ALL your plugs are firing properly? I got a little lost with your previous statement of testing EGI and it worked and didnt work at the same time, and that your fuel pump doesn't come on at all unless the circuit is jumped. Is this something new thats happening? Cause last I remember you were getting 30 psi and I don't think you had to jump the circuit?
10-14-09, 02:11 PM
#40
Ok latest update: I got the car started, but after alot of cranking...I had to put 12V directly to the pump again....There was alot of fuel vapor everywhere and it only ran for 30 seconds and shut off....But when I jumped the diagnostic connection at one point in time my engine fuzxe under the dash burnt out hence why I wasnt getting any pressure or voltage..replaced that and I was back up to 20-30psi at the rail but the car wouldnt start...
Either way I am getting new relays and a fuel pump resistor and a fuel pump harness. I am actually giving up on my diagnostics and takeing the car to banzai to have Chris help me out on this problem....I have spent way too many hours and have not gotten anyywhere....so I apperciate yourericate your help and will update you next week what Chris finds out for me.
Either way I am getting new relays and a fuel pump resistor and a fuel pump harness. I am actually giving up on my diagnostics and takeing the car to banzai to have Chris help me out on this problem....I have spent way too many hours and have not gotten anyywhere....so I apperciate yourericate your help and will update you next week what Chris finds out for me.
10-14-09, 02:14 PM
#41
There is no need to perform the fuel pump rewire mod, if I can't even get the power to the pump the stock way....This is almost like the boost a pump essentially...and I have that in the car but disconnected it since I wasn't getting my normal voltage to the pump as it is.
10-16-09, 10:04 PM
#42
So as I was thinking the fuel pump resistor may have been bad due to it's high resistance. Well I jumped the pinout on the diagnostic connection with the fp resistor pluged in I would get 22 psi of rail pressure. In terms of voltage I was at 7.5 volts. But then I unpluged the fp resistor and descided to jump the harness and all of a sudden I get instant 40 psi. That pretty much explained my fp resistor is bad.
Now here's my question when the key is on and you don't have the diagnostic pins bridged would you really see 38-40 psi? Reason I ask is because the system though would just prime and then stop with the pump priming there for u lose pressure. Please help clarify? Now I dint know what next do I need to look at.
Thanks guys
Now here's my question when the key is on and you don't have the diagnostic pins bridged would you really see 38-40 psi? Reason I ask is because the system though would just prime and then stop with the pump priming there for u lose pressure. Please help clarify? Now I dint know what next do I need to look at.
Thanks guys
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