vvhitewabbit

All right here is my dillema.

88 conv. fresh rebuild, fuel pressure 42psi when check connector connected and ign. on, compression a little low sitting at around 80 front and rear, have spark, get fuel, little confused.

Trying to start the car after rebuilding and it gets ready to start then it just doesn't i keep cranking it over and still nothing so i do the unflooding stuff and crank over sounds better then goes back to not sounding so good. So i decide to check my spark plugs, pull one of the wire and plug out of the engine put an old one in, *unplug the fuel pump*, crank over to see if im getting spark. I do and the car almost starts so i plug the wire back in keep the fuel pump unplugged crank it over and the car starts for 2 seconds then dies, but it is like a really hard start.

So i got a fuel pressure tester to see what is going on. So plug it in and crank the car and get 38 psi without the jumpers connected for the yellow connector. Psi holds at 30 when the car is off. Yellow connector connected and i get 42 psi---are these numbers good cause the fsm says 64-80something with the jumper wire in but the haynes manual says 34-39---It just seems the engine floods when everything is connected normal.

I thought it could be the injectors but from the 3 sets i get the same results. I tried doing a switch so when the car started flip the switch tothe fuel pump to turn it on, still just dies. when i connect the fuel pump directly to the battery i get 75psi but through the factory wiring i get 38 psi, could the pump be bad, could it be something i just overlooked, guys im so close to getting this car going but i am just completely out os any ideas what it could be any insight I will appreciate

RETed

Ignition timing not "zero'd"?


-Ted

vvhitewabbit

you think that would be all that is wrong?

Mobius

Typically a low compression rebuild will be hard to start. So the reason its flooding is that fuel isn't being burnt up at the correct rate to start it = drenched plugs. If you were having fuel pump problems like a severe lack of pressure then your plugs wouldn't be getting drenched at all.

Now the reason that you might be assuming that the car is wanting to start with the fuel pump unplugged is because actually, whats happening, is that the fuel is being restricted and thus not flooding the combustion chambers and *almost* reaching the right air/fuel mix to the compression your generating, to *almost* fire.

Sometimes when people experince flooding on new rebuilds people will take vice grips or channel locks to the one of the fuel lines to completely cut off fuel for a couple of seconds to alievate, temporarily, flooding so that it will start. Same thing your kinda doing with the unplugged pump. My 91 has a fuel cut off if you press the gas pedal all the way to the floor...

Ted may be right. without a Zero'd ING. your situation becomes that much worse. Especially at low compression.

On a rebuild I recently put together I accidentally matched the CAS mark to the pins that hold the geer at the bottom of the CAS on, instead of the little indented circle above the geer teeth on the shaft.

Once I realigned it, it fired up.

You may also have to put some Automatic Tranny Fluid in your engine to help add more compression.

Good luck

vvhitewabbit

Thanks guys im going to try my CAS and see what happens. Ill keep you posted

HAILERS

****and the car starts for 2 seconds then dies, but it is like a really hard start. ****

Those words are exactly why you NEED to make a fuel cut off switch. Even if it's a temporary one that intercepts the blue wire that feeds the fuel pump plug.

The concept behind the switch is that when the car starts for those two seconds, you have the switch in you hand and you can immediatley switch the switch back to FUEL PUMP ON, as the engine fires up for those two seconds.

Other than the timing mentioned above, you might want to take a half hour time out and examine your engine, looking for large hose being left off. A common one is the feed line under the bac and the feed line on the back of the manifold that feeds the brake booster.



Take to heart the temp fuel cut switch if you find the timing to be in the ballpark.

vvhitewabbit

Hailers I did try the fuel cut off switch but cam up with no success. turned it off and it started so i switch it on and got fuel pressure but the car still died.

vvhitewabbit

Hailers I did try the fuel cut off switch but cam up with no success. turned it off and it started so i switch it on and got fuel pressure but the car still died.

vvhitewabbit

alright i tried ted idea about the cas not being zero'd, no differance same thing, then i tried the red align mark instead of the yellow same thing, tried the fuel cut switch, no different result. after trying to start the car with the pump connected pulled the plug but it wasn't drenched like i was thinking it was being flooded its not. Next im going to try connecting the pump directly tothe battery and see what results i get
Oh yeah now the fuel pressure will not hold after the car is shut off, crank it over and i get about 40 psi, it attempts then i stop and then the pressure drops really fast, i have no leaks around the engine and no gas smell, Could the FPR be the culprit all along. What do you all think Let me know.

HAILERS

Is it possible that you have the fuel lines connected backwards?????

Your explanation of what the fuel pressures were in your first post left me confused.

If a gauge is connected directly to the outlet hose on the filter.....the pressure should read the 64 plus that you read in some manual.

If the fuel gauge is TEE'D into the fuel inlet line after the filter (meaning now the whole fuel system is in the circuit), then the pressure should read b/t 28 and 40 psi when the key is held to ON or the jumper is in the yellow plug. Anywhere b/t those figures is plenty good to start the car.

I suspect the fuel lines are crossed. We've seen that numerous times on this site. I thik sometimes that is due to a Jspec engine being opposite to a USA engine as far as the fuel line arrangement goes.

Mobius

i have no leaks around the engine and no gas smell, Could the FPR be the culprit all along. What do you all think Let me know.

From all of the rx7 that I've owned (4), Iv'e done two successful rebuilds and tons of work on n/a. I have never encountered a fuel pressure regulator as a problem for start up.

Now just for clarification, are your plugs being drenched or not?

Correct me if I'm wrong but if you're lines are crossed, that means that the pump would be fighting against the fuel filter, as the filter should be designed to let fuel travel in only one direction. This would definately cause problems because you wouldn't be getting any fuel at all. When rotary floods, its been my experience that you can smell fuel from the tail pipes. Sometimes white misty comes out...Anyway, if it is flooding, then that's great! you know you're getting fuel.

Realistically, if you're getting it really close to starting, and this is your first rebuild, then don't make yourself crazy with problems that might not exist. Next thing you know you'll be replacing perfectly fine components, discontecting-reconnecting stuff and possibly adding problems by forgeting what you did to it and didn't to do it.

Its is very very typical for rebuilds to be a pain in the *** to start up at first, especially for the newbs. I am not surprised you're experiencing this...Its perfectly normal.

It may seem that the twenty times or so that you've spent trying to start it is excessive and this would lead you to think about other faulty parts....to some extent this makes sense.....But reading all the times other people have had this same exact problem and experiecing it myself on a new rebuild recently put together I'd say don't worry it will come. Just be patient.....As with most of these cases including mine, the compression was low and we all spent the 200 times or so cranking it until we got just right. Some people have had their buddies with diesels tow start their rides before it worked.

So I would really encourage you to once again varify you have fuel as per hailers suggestion. Make sure you got spark. And then figure out a way to get more compression. Any engine needs those three things and any engine will run: Fuel Spark Compression.

If your compression is low you might want to think about the ATF to boost your compression. Low compression, in my opinion, is the #1 culprit for hard starting in new rebuilds. The ATF may sound like a stupid idea, but its what I had to do to get my first rebuild to start after about the 40,000 time it didn't start.

HAILERS

****but it wasn't drenched like i was thinking it was being flooded its not.*****

vvhitewabbit

the fuel lines are not crossed, that was one of the probs before. I got that straighten out. The plugs are NOT drenched, fuel pressure reads as followed....

Gauge directly to fuel line and factory wire harness(no t valve) reads 42psi

Gauge with t valve inline and wire jumpered reads 42psi

Gauge with t valve inline wire NOT jumpered, cranking over reading 38psi

Gauge with t valve inline car turned off lose all pressure in about 20 seconds

Car seems to start when the pressure is about 10-15 psi
And when I try to start the car when everthing is hooked up and crank it for like 10 seconds the plugs are NOT drenched but around 10 seconds the gets a diif sound almost like too much fuel is being injected in the engine, pull the plug and find very little fuel on the plug.

Ill try the atf thing but i am almost absolutely sure the FPR is shot since it is not holding pressure after the car is shut off

thanks for all your guys help-Ill keep you all posted

vvhitewabbit

Forgot to tell you ....

Gauge directly in the line NO t valve pump wired directly to the battery i get about 75PSI

vvhitewabbit

Okay i have tried a few other things to get it started. I tried wiring the pump dircectly to the battery and still nothing. Used a timing light when cranking the car and the leading wire is dead on with the yellow mark. here is a list of everthing that I checked:

1-Timing is good

2-getting spark

3-getting fuel

4-pressure is about 38 PSI

5-compression is sitting about 65 on a fresh rebuild

I'm gonna try the compression thing as per mobius and see if if that is the problem, is there anything else that im missing here guys please let me know any input is REALLY, REALLY appreciated im geting loss an what else to do and to check. Ive gotten this far on this car and im definately not going to give up so please keep the suggestion coming

Mobius

I bet once you get the ATF in there it'll start up on the 3rd or fourth try.

This is how I do the ATF thing.

I take a oil can that can squirt atf into the spark plug hole. You'll need to do it to the trailings because those holes allow a small enough neck to get all the way into the combustion chamber, the lead hole will not work.

I take a small screwdriver and place it in the trailing hole so that I can tell when a combustion cycle is ready to accept about a table spoons worth of atf.

That is: Once I've squited it in, about three squirts for <i>my</i> oil can, I gently stick the screw driver in and gently turn it until its starts to cycle over so I can squirt Atf in again. I do this until I get all three sides of the rotor for each housing.

I also let it sit for about 10 - 15 minutes before I attempt the first start up.

Hope that helps.

Mobius

EDIT

Whoops

Got the lead and trail holes mixed up.

So you'd use the leads as its the bigger hole.

ROTILLA

DRAG it untill it starts. In 2nd gear first, if that doesnt help, do first gear. I had to do this on a first gen I had. My dad and I hooked it to his truck, and drug it key on in second gear for 2 blocks( got going pretty fast), then it started, and then ran fine from then on. My dads idea........; )

vvhitewabbit

You guys are awsome i put some atf in it last night and im getting around 85-90 psi in the rear got tired and didn't check the front ill keep you posted and definately let you know what the outcome is, thanks again guys

vvhitewabbit

Mobius you are a genius, the atf trick worked like a charm. The beast started up almost on the first crank but I do have another problem. it starts, runs for about 2-3 seconds then you hear a click the fuel pressure dies then the car dies. The click sounds like it is coming from the dash

Mobius

it starts, runs for about 2-3 seconds then you hear a click the fuel pressure dies then the car dies. The click sounds like it is coming from the dash

Never had a problem like that before. Hailers or NZ would probably know more about this than I.

If they don't show up for suggestions my guess would be that a "clicking sound" would indicate a relay problem.

Under the "Fuel and sub zero assist" bookmark in the .pdf the diagram shows that there are three relays that are related to the fuel system.

The circuit opening relay
the main relay
and the fuel pump relay & resistor

Here's where that diagram can be found:

http://www.iluvmyrx7.com/2ndgen/manu...ng_diagram.pdf

I would start by checking the relays out. The first one I would start on would be the circuit opening relay because its name is the coolest, and it's easy to check. That and I have no idea where the other relays are.

The directions for checking the circuit opening relay is here:

http://www.iluvmyrx7.com/2ndgen/manu...systems_na.pdf

Its directions are under the bookmark "fuel system."

Hopefully NZ or Hailers will come by and tell me I'm all wrong and have some other more easy solution. All I have to go off of is that your observations seem to indicate a problem that isolated to the fuel system. Do you notice a voltage drop from the fuel pump at the same time? If the fuel pump is being electrically shut down for some reason I'd say the relays are a good place to start. If you hear a click from the dash the circuit opening relay is right by the master brake and master clutch cylinder.....

Might want to give it a day or so, for some other suggestions too.

vvhitewabbit

I actually got it started and idling for a good while till it got hot. The ecu did throw out the water thermo sensor is no good so im going to replace that 2-morrow.
I did do direct power from the batt to the fuel pump that is what kept it going and got it started. So i tried to hook it up factory style and when the click happened it lost fuel presur really fast so my guess is a relay. Also when i try to give it gas its almost like it doesnt want to get that high, goes to like 4000 rpm but no more. So im going to see if the thermo sensor does the trick or if the ecu will throw out another code but we will see what happens thanks again mobius.

WAYNE88N/A

the clicking you're hearing is coming from the fuel circuit opening relay, it's probably losing its ground from the AFM switch...try jumpering the check connector near the right strut and see if that helps...read out the first two pins on the AFM connector (on the AFM, not the harness)(if looking at it from the left side of the car), you should get an open until you push on the "door", then you should get continuity...edit: yeh, that "it goes to 4000 and no more" sounds like what happens when that thermo sensor goes out...

Mobius

Ah-HA!

the clicking you're hearing is coming from the fuel circuit opening relay, it's probably losing its ground from the AFM switch...


someone else who thinks it could be the click of a relay.

MR. Burns......excellent

If the circuit opening relay is wigging out then maybe its also affecting the continuity of the fuel pumps operation under normal circumstances? Or as Wayne pointed out, if its messing with the AFM then you'll definately have problems getting the right air/fuel mix, thus crappy throttle response.

vvhitewabbit

Thanks again guys, Mobius and Wayne you are both awsome. So I use an ohmeter on the two left connectors of the AFM then thats about the point i get lost at, If the FSM has it I should be able to figure it out if I'm missing something please let me know. I have a few other things i need to work out before i drive it-oil cooler lines leaking like crazy-but im sure it'll be a blast to drive when it is all done