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And I wouldn't go to the auto part store for cable, go to a welding supply and get the lengths you want. What I've seen in the auto stores is way over priced and is usually more like 4ga or 6ga.
Don't count on good grounding by grounding the engine to the firewall and then the batter being in the back of the car only grounded to the chassis. This can work, but that's how some people get weird electrical gremlins.
One 2ga wire to the chassis, and one long 2ga wire to the engine block. No chance of battery relocation related grounding issues if you do that.
And I wouldn't go to the auto part store for cable, go to a welding supply and get the lengths you want. What I've seen in the auto stores is way over priced and is usually more like 4ga or 6ga.
Don't count on good grounding by grounding the engine to the firewall and then the batter being in the back of the car only grounded to the chassis. This can work, but that's how some people get weird electrical gremlins.
One 2ga wire to the chassis, and one long 2ga wire to the engine block. No chance of battery relocation related grounding issues if you do that.
Compression is OK (haven't tested it since last summer to be honest). I'll get at least a 2g wire and shorter than what I had before.
Positive cable is 2g and is in apparent very good condition.
Not sure a timing light will help. It's basically computer controlled, which means either it's your computer (i.e. tune) or the signal to the computer (crank angle sensors and CAS wiring). Easy first check is making sure the G and NE connectors are correct.
Not sure a timing light will help. It's basically computer controlled, which means either it's your computer (i.e. tune) or the signal to the computer (crank angle sensors and CAS wiring). Easy first check is making sure the G and NE connectors are correct.
Originally Posted by cr-rex
White plug on top and grey plug on bottom
And I reinitialized the PFC so there's no more tune...
Fix your fuse/electrical problem and then post up compression test videos if it still won't start.
Compression test video is next, as soon as I find someone...
Originally Posted by Narfle
Are there any local rotor heads in QC? Seems like some beer and pizza and some buddies might could help.
A well-known rotary shop is 100 miles away. I would HATE having to do that. I moved 300 miles away last summer so I lost all my local friends.
This morning I bought a ground cable. 2 feet long instead of 3 feet. 1G instead of 2G. New instead of old. I cranked the engine for the first time today, went up to 600 RPM on the first second (as usual, it always explodes when I let the car sit for hours), then no explosion whatsoever. I didn't blow the 200A (didn't crank long enough anyway). Engine now cranks up to 182 RPM.
I also sprayed starting fluid into the throttle body, without success.
Homeworks:
Post compression test video.
Check resistance between positive cable and ground points (starting circuit).
Did you check your CAS sensors? Did you check your trigger wheel (on correct? bent or broken tabs?) Did you check the wiring, not just whether you have the connectors on right?
You can't just assume ****
(well, you can at first but when you've troubleshooted all the easy stuff, you need to start walking it back)
Did you check your CAS sensors? Did you check your trigger wheel (on correct? bent or broken tabs?) Did you check the wiring, not just whether you have the connectors on right?
You can't just assume ****
(well, you can at first but when you've troubleshooted all the easy stuff, you need to start walking it back)
I did not check the CAS sensors, trigger wheel and wiring. I will try to do that right now.
Someone sent me a PM suggesting that there could be a problem with my fuel pressure. I like the idea.
I installed a new Walbro 450 LPH fuel pump. I've got stock injectors and I deleted the FPD. Fuel pressure is high (fuel pressure gauge is installed right now) but I thought the injectors would do the rest of the job to control the flow. Could I be mistaken?
What's you fuel setup like? Base pressure should be 43psi, iirc. What sort of pressure are you seeing? What kind of regulator do you have? How old is the gas?
Can't remember if you tested this or not, but are the feed/return fuel lines swapped? I worked on a car once that had that, it would try to start but never actually would. Some fuel would go backwards through the FPR but not enough to actually run on.
What's you fuel setup like? Base pressure should be 43psi, iirc. What sort of pressure are you seeing? What kind of regulator do you have? How old is the gas?
Fuel setup is all stock except for the Walbro fuel pump and FPD deletion.
Gas is brand new, I pumped old gas out, poured new gas in (without 2-stroke oil).
Regulator is stock, BUT... (I'll answer the other replies first).
Originally Posted by BLUE TII
I also have Walbro 450 on otherwise stock fuel system.
Runs a bit richer from FPR over running 43psi (as you found), but no starting or running issues.
Very good to know, I'm having pretty much the same setup, except that my FPD is gone.
Originally Posted by DaleClark
Can't remember if you tested this or not, but are the feed/return fuel lines swapped? I worked on a car once that had that, it would try to start but never actually would. Some fuel would go backwards through the FPR but not enough to actually run on.
Dale
Well they were swapped at first (last year) but now they are OK... Feed line to primaries, return line to secondaries.
Some people mentioned the FPR here and I wasn't sure of what they were talking about (and that's a good thing). So I searched vacuum diagrams, and I found out that the nipple on the FPR is disconnected.
The part that I circled in red, how do you call it? A solenoid? I remember it was (somewhere) before the rebuild, but I didn't install it back (I didn't know what was its purpose, and I still don't know). So I have to connect a line from FPR to that solenoid, then another line from that solenoid to the UIM? Could it be the reason to my problems?
The fuel pressure regulator uses that vacuum line to raise and lower fuel pressure dependent on intake manifold pressure. You have a base pressure (I THINK it's 38 psi or so) and that is your pressure with the pump running and intake manifold vacuum at zero.
If you have vacuum, the fuel pressure goes down. Boost, it goes up. This is to maintain a set positive pressure above the intake manifold pressure. Think of it this way - if the intake manifold had 38 psi of boost and the fuel was trying to squirt into the engine at 38 psi, it wouldn't do anything. For the fuel to squirt out it has to be going from high pressure to low pressure.
Stock there is a vacuum solenoid between the FPR and the vacuum line on the intake manifold. When the car is hot, the solenoid switches to atmospheric pressure (the little filter on the solenoid) so the fuel pressure is bumped up a little bit. This helps in hot starts since you can have fuel boiling in the rail, the extra pressure helps that out.
If memory serves there is a nipple on the LIM pointing back towards the firewall, that is where the FPR solenoid pulls from. Look at the full vacuum diagram to check.
Also, the FPR should be what the return line is hooked to. Fuel comes from the pump, through the primary and secondary, the FPR restricts flow to set the fuel pressure, then excess fuel goes past the FPR back to the tank.
It's easy to get confused at the hard lines coming from under the car as to which one is which. If your car is modded that can make it even more confusing.
To be on the safe side I would maybe pull the feed line off, put it into a bottle or something safe, and run the fuel pump for a few seconds. If you see fuel pumping out you know you have the feed.
The fuel pressure regulator uses that vacuum line to raise and lower fuel pressure dependent on intake manifold pressure. You have a base pressure (I THINK it's 38 psi or so) and that is your pressure with the pump running and intake manifold vacuum at zero.
If you have vacuum, the fuel pressure goes down. Boost, it goes up. This is to maintain a set positive pressure above the intake manifold pressure. Think of it this way - if the intake manifold had 38 psi of boost and the fuel was trying to squirt into the engine at 38 psi, it wouldn't do anything. For the fuel to squirt out it has to be going from high pressure to low pressure.
Stock there is a vacuum solenoid between the FPR and the vacuum line on the intake manifold. When the car is hot, the solenoid switches to atmospheric pressure (the little filter on the solenoid) so the fuel pressure is bumped up a little bit. This helps in hot starts since you can have fuel boiling in the rail, the extra pressure helps that out.
If memory serves there is a nipple on the LIM pointing back towards the firewall, that is where the FPR solenoid pulls from. Look at the full vacuum diagram to check.
Also, the FPR should be what the return line is hooked to. Fuel comes from the pump, through the primary and secondary, the FPR restricts flow to set the fuel pressure, then excess fuel goes past the FPR back to the tank.
It's easy to get confused at the hard lines coming from under the car as to which one is which. If your car is modded that can make it even more confusing.
To be on the safe side I would maybe pull the feed line off, put it into a bottle or something safe, and run the fuel pump for a few seconds. If you see fuel pumping out you know you have the feed.
Dale
Thanks a lot for the complete explanation!! If I understand correctly, I can keep it unplugged for now. And I'm not sure where the solenoid is supposed to be exactly. I think the only solenoid I've got on the rat's nest rack is right behind the alternator.
I double-checked the feed line by taking it off. Feed line and return line are confirmed to be connected at the right place.
I just did (another) video of the fuel pressure. It's exactly the same as the one I did in September 2019 (with an explosion at 0:09, which is quite rare).
Well, compression is definitely low right now. Same numbers on both rotors. I just unflooded the car and charging the battery right now. Tomorrow I will pour some transmission oil in both leadings and try again with a fully charged battery.
Guys I think I'm getting there. Compression more than doubled with a charged battery and some transmission fluid. And I found something very interesting.
There's a ground from the charging system that is connected with a bolt of the ABS module... And the bolt is loose! Do you guys know where it is supposed to go? Now I guess it really could be the reason why I keep blowing fuses? Please yes!
Ok. Just looked at your pic again. I was looking at the wrong spot. I believe your loose connection is the other end of the wire I was pointing to in my pic
But now that I think about it. I think that end goes to the bolt for mounting the starter to the engine/bell housing.
Last edited by TwinCharged RX7; 03-14-20 at 02:19 PM.
Ok. Just looked at your pic again. I was looking at the wrong spot. I believe your loose connection is the other end of the wire I was pointing to in my pic
But now that I think about it. I think that end goes to the bolt for mounting the starter to the engine/bell housing.
Yes I think now it makes sense! Top bolt of the starter I suppose?
And also I'd like to add another thing. I'm not sure why I seem to be finding all the problems today.
That wire also seems to be wrong, but I couldn't find it in my spare wiring harnesses. Do you have any idea?
I'll try to search, it is so simple but yet so hard to find. Thanks a lot for your help!
03-11-20, 09:57 PM
