Mdhwoods

Was given the 88 RX7 from my dad who only started it once in a while. Mostly sat in the garage for the last 10 or so years. He was the original owner.

It was running fine when i got it with the exception of the 3800rpm hesitation. My goal was to track that down this winter when i had time but continue to drive it a few times a month. Ive researched that its possibly the secondaries or a ground issue. Leaning towards the secondaries since he rarely drove it and probably never got them to fire.

Took it out Saturday night. Started fine. Let it warm up for about 5 minutes. Hopped in and got on the freeway. Was doing about 75 in 4th when she just quit. Electrical was still up but engine was not. Got it over to the side and tried to start it. Turned over fine but acted like it was out of gas. Gauge read 1/4 but i remembered my dad saying he didn't think the gauge was working properly. Called a tow but they were 2.5 hours out so I had some friends come get us and we went on with our dinner plans.

Had the friends take me home and picked up some gas. Wife took me back and i put about a gallon or so in. Unfortunately the batter died pretty quick so i still had to wait for wrecker. We tried to jump it but it wouldn't go so i had it towed home.

Put the battery on a charger and the next day put another gallon of gas in. Turns over strong but no start.

Gonna check fuel pump soon as it warms up. I have a fuel pressure tester. When the pump goes on an RX7 do they usually just go? There was no sputtering or hesitation on the engine like a piston engine would do before it happened. Car just died. Can I tie my tester in right after the fuel filter?

2nd, I want to check the compression but cant get it running to get reading when warm. What can I expect on a cold engine for them to read and the car still start? I know over 100 on a warm engine is what we are looking for.

Car has about 115k on it and no mods at all. It is completely stock.

Thanks in advance.

satch

iTrader: (1)

The filter or primary injectors could be clogged but it's probably something else. The pressure tester can be placed after the filter or coming off the engine using the outflow hose as it travels back to the fuel tank.

You could have also blown a fuse integral in keeping the car running. On your car that would be both EGI fuses in the engine bay fuse box along w/the 15 amp engine fuse in the interior fuse box. There is a Green check connector near the lead coil which has four wires. One of these wires is B/W. W/key to on it should read 12 volts. If it does then the EGI 30 amp Comp fuse is good along w/the engine fuse. To check if the 40 amp EGI inj fuse is good pull the two wire plug off of the lead coil and w/key to on the Black/Yellow wire should also have 12 volts.

The fuel pump does not turn on w/key to on unless the fuel check connector was jumpered or the AFM flapper door was open, otherwise the pump turns on w/key to start.

Evil Aviator

Yes, it usually just stops working, resulting in the symptoms that you have described.

It could be a grounding issue.

If the secondaries stopped working when the engine was under load, then the engine blew and needs a complete rebuild. It doesn't sound like that is the case. If the secondaries stopped working and the engine isn't blown, then it would still start just fine, which it doesn't. I wouldn't worry about checking the secondaries right now.

chuckproto

iTrader: (9)

Look at the spark plugs to determine if theyre getting fuel.

Mdhwoods

Great info thanks for this. Ill check the electrical 1st since that's easier then the pressure test. I read that about the fuel pump only being on when key to start then the afm flapper keeps it on after. Is the fuel check connector by the intake manifold? Tried to find some into on where its at as i don't want to jump the wrong one.

satch

iTrader: (1)

It's by the boost sensor. Plug is Yellow encased in a Black rubber boot. Two wires that are Brown and a Black. You could also jumper the bottom two wires of the circuit opening relay located under the dash and just to the right of the steering column. Yellow and Black in color featuring five wires (3 on top row and 2 on the bottom row).

Mdhwoods

Fuses all good. 12v at both test points. Pulled fuel line. Put pressure tester and jumped yellow plug by passenger side. Hear relay click under dash no fuel pressure. Next I need to get to fuel pump and see if I have 12v when jumping plug. Looking like fuel pump could be culprit. Good place to pick one up? Or recommended brand if that's what it turns out to be?

Thanks

misterstyx69

iTrader: (142)

Just get a replacement stock pump unless you intend on altering your system which would require getting rid of the stock regulator,etc as your new "better flowing" (I will assume) pump will just overwhelm the stock regulator and you will then be faced with more problems.
You can find used pumps on Forum in the appropriate For Sale section or Ebay.
I have to warn you to Please,Do not use this Section to even HINT of asking or this whole Thread will be suddenly die..like your pump!(Rules,rules,rules.).
Best of luck to ya.

Mdhwoods

Have voltage at the fuel pump plug in the trunk when test connector is jumped. You say in the for sale section or on eBAy. I take it you can only buy used? No aftermarket oem available new? Have not had to buy parts for a 26 year old car so just trying to figure out how this works.

Thanks

satch

iTrader: (1)

While you have voltage to the pump, you might have a bad ground at the pump. The connector that plugs into the pump has a Black wire which is the ground. Make sure it's good. The ground wire coming out of the rear harness connector bolts to the body very near that area. If need be supply another ground to the rear plug connector to see if that gets the pump to turn on.

Mdhwoods

Will do. Do I have to take all those pesky clips and all inner plastic trim to get easy access to the plug. I hate those clips. Also,12v at the plug? Mine seemed closer to 10 and I know there is a resister in there.

Thanks

satch

iTrader: (1)

The plug location might just be under the carpeting or it might be hiding underneath the fender well carpet panel (left side I believe). The ground wire that feeds to the connector plug should be fairly visible and that should lead you to the connector. You can also locate the ground where it bolts to the body and place a meter lead to it w/the meter set to ohms and the other meter lead to the body and the meter should read a very low number.

Mdhwoods

Oh I found the plug. Ite behind the plastic trim in the trunk. Pia to get to as I gave to take all those dam plastic clips off to get the trim off. Is 10v normal with car not running at plug?

satch

iTrader: (1)

Pretty much.

Mdhwoods

Now that I got out there in some daylight I was getting 11.3v at the plug for the pump. Battery is a bit low now so i need to charge that up as its at 11.5. Id say the pump is definitely bad. Seems there are a lot of aftermarket pumps. Is one brand better then the other? Ive seen them from 40.00 to 200+. Not asking where to buy just if one brand will serve me better then another. My ground is also fine as my ohms were below 5 to ground.

thanks

satch

iTrader: (1)

If you have an NA be careful to not get a pump which will over fuel your current set up. Walbros are good but I'm not sure if they make replacements for NA's, but if they do then that would be a good fit.

Mdhwoods

NA being naturally aspirated or north ameriacan. Non turbo? I found a desno new that's for my car. Hopefully that will work. My car is North American non turbo. Site said the pump I bought was for my car.

satch

iTrader: (1)

Yes.

misterstyx69

iTrader: (142)

Just wanted to jump in and say that I was trying to point you towards either a Ebay pump or a Used pump for a good reason.
Go to the dealer..see what they want for a Pump..
You can pretty well buy a CAR for that price.(at least I can.)

N/A= normally aspirated.
TII= turbo engine'd Series 4 or 5 car.

Also the fuel rails have the regulator and a Pulsation dampener built in to the rail so If you change the Pressure of the Pump(get a Higher flowing pump) then you need more parts to compensate for that.(car won't run correctly with higher unregulated fuel.The higher pressure pump would overwhelm the stock regulator)
That is why I am saying to Stay within the stock parameters.If not you just compound the problem.Why buy more parts if you just want to get the car running.(not modify it ).

Now,Parts wise: I was Pointing you to the For Sale section..
Why?...Ralph needs new shoes!
(no seriously,guys do turbo swaps out all the time and the N/A pumps sell like a dime a dozen).

Mdhwoods

Hahah, love it. Ill have to see if i can help Ralph out at some point. Pump i got should be an equal replacement.

Thanks again for the advice.

Mdhwoods

Fuel pump replaced and car back up and running. Couldn't believe the condition of the prefilter on the pump. Not sure but it could have been the original. Covered in a white flaky substance and had some tears in it. Fuel filter is next. Can that be replaced from the top or do you need to get the lower line off from underneath? Also there was this black rubber boot covering the positive terminal on the pump lug. It split off in my hands. Is this a critical part or just a safety measure.

Now off to the 3800 hesitation.