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The TPS probably won't matter, I think the ECU ignores it during cranking and warmup.
It's a good idea to get everything as close to "normal" as you can just to eliminate possibilities. The ECU does have a wire that it uses to sense that the key is in the "start" position and the car is cranking. This may also affect whether the fuel pump runs, since the pump doesn't run when the ECU doesn't see the engine turning. Not 100% on that.
With the green thermosensor disconnected, the ECU assumes a default of 176° F coolant temperature. So there is zero cold-start or warmup enrichment being applied. It's more likely that it didn't have enough fuel than that it flooded, though anything is possible.
So in short, plug in everything you possibly can first. Then try diagnosing if it still won't start. Otherwise you'll be chasing every disconnected sensor trying to find the problem.
Alright thanks, I’m pretty sure the thermosensor is connected but functional I’m not sure about. I’ll check that first and then fix the wire on the starter as well as hook the air intake back up.
I got the starter to work on the key and put all the intake piping up to the air filter on. I noticed a check engine code that turned out to be for the thermo sensor, turns out it was unplugged. I plugged it in and cleared the code but if I understand right it takes a while for it to come back. Checked spark and it has really good spark though the plugs seem pretty old. Crank Crank Crank, pull plugs, seem oily but not gassy. Add oil, crank crank crank, nothin. If I add starter fluid itll sputter to life but won't keep running. I can't seem to get it to use the fluid it just puddles wherever I put it. I probed where the Thermo sensor is supposed to be connected on the ECU plug and my meter reads 0.01 volts??? The fsm says idle engine cold=.4v-1.8v and 68F =about 2.4v. Im thinking about getting a new one, but wouldn't this put it into cold start mode being low like that, id expect overfueling not under?
I got the starter to work on the key and put all the intake piping up to the air filter on. I noticed a check engine code that turned out to be for the thermo sensor, turns out it was unplugged. I plugged it in and cleared the code but if I understand right it takes a while for it to come back. Checked spark and it has really good spark though the plugs seem pretty old. Crank Crank Crank, pull plugs, seem oily but not gassy. Add oil, crank crank crank, nothin. If I add starter fluid itll sputter to life but won't keep running. I can't seem to get it to use the fluid it just puddles wherever I put it. I probed where the Thermo sensor is supposed to be connected on the ECU plug and my meter reads 0.01 volts??? The fsm says idle engine cold=.4v-1.8v and 68F =about 24v. Im thinking about getting a new one, but wouldn't this put it into cold start mode being low like that, id expect overfueling not under?
That definitely seems like it's a problem. The voltage looks like it's out of range.
The ECU has a fail-safe, which is that when the sensor is disconnected or out of range it assumes the temperature is 176 degrees F. So if the sensor is failed it will lead to under-fueling when cold. The benefit is that when the car is warmed up, you can drive around all day with the sensor unplugged and the ECU won't care.
EDIT: Quick test, does the car behave any differently with it disconnected? Does the voltage at that pin change?
Alright, I was under the assumption that the voltage raised as the car warmed up from 1.8 to 2.4
Looking at it again, you may be right. It says "Idle (Engine Cold): 0.4V-1.8V", and then "Water temperature 20C (68F): 2.4V". So maybe it should be at 0.01V if it's cold enough. I don't know what measurement shows on that pin when the sensor is failed though, so I'm not sure.
I've only ever tested by removing the sensor and using a heat gun to watch the resistance change, but unfortunately you need to drain the coolant to do that.
Yes it is I just remade the bracket why do you ask? I think my next course of action is to try and take the thermosensor out/measure resistance somehow.
1000% it can never get clean, Maybe because I hadn’t started working on the car in that picture. I will say I am very fortunate to have the shop space I do.
I pulled the CAS and pushed on the AFM while I spun the CAS, and took THIS video here. You can here a faint clacking sort of blinking in and out I believe that's the injectors but even after all that clicking and fuel pump running when I tried to start it the plugs were still dry and no pops were made. Thermosensor ohmed out just fine (I removed it). But when I measured the voltage at the ECU I got -12 volts with the sensor connected but still ohmed out alright at 3k ohms, not to brag about my heated shop or anything. So according to the internet for the voltage drop to occur the other end needs to be connected to something, so im guessing to get the FSM spec is for probing the connector when its connected ill try it later. My next guess is fuel pressure maybe, I can hear fuel flowing when the pump is on but I don't know if the regulator is just passing it all over.
Are you sure the timing is set right? It's been a long time for me with FC's and you should search to verify. Line the yellow mark on the pulley up with the tit on the front cover and pop the blind cover on the CAS. The tips of the CAS rotor should be aligned right before the pickups. Again, search to verify.
Even without fuel it should start and run on fluid, not just sputter.
Thats how im setting it, if the yellow mark is the first mark on the pulley. If you watch the video I counted that as burning all the fluid we gave it though I could be wrong. It’ll definitely run on starter fluid but I was trying to spray it through the afm and it seemed like it wasnt going anywhere. When I sprayed through the throttle blades it burnt it.
Thats how im setting it, if the yellow mark is the first mark on the pulley. If you watch the video I counted that as burning all the fluid we gave it though I could be wrong. It’ll definitely run on starter fluid but I was trying to spray it through the afm and it seemed like it wasnt going anywhere. When I sprayed through the throttle blades it burnt it.
Pull the AFM, give it a solid shot into the intake tube and then put the AFM back on. Your video didn't work for me, the link is not open to the public or blocked by my organization.
Have you verified that you're getting fuel to the rail and if you've done that have you checked base pressure?
Pull the AFM, give it a solid shot into the intake tube and then put the AFM back on.
That’s what I’ve been doing, it’ll run for a little bit but once it runs out of fluid(fairly soon) it’ll just die. My plan today it’s to check fuel pressure/flow and maybe pull the fuel rail.
Molotovman brings up a good point with the timing. It will usually run with the timing pretty far out, but it's good to get it dialed in to eliminate that possibility.
When you installed the CAS, was the dimple on the bottom CAS gear aligned with the pointer on the body of the CAS?
There are a few things that need to be aligned:
- Front pulley at first mark (yellow) aligned with pointer. Which you say you've done.
- Dimple on the bottom drive gear on the CAS aligned with the pointer on the aluminum body of the CAS.
Then, with the cover off, try to install it as straight as you can. Watch the tooth alignment inside for reference, so you can see if it moves when you install it. As it slides home, it will always move a bit, but it should land more / less in the middle of the adjustment slot. Adjust it so it matches what it looked like with the dimple aligned, and then gently tighten the lock nut.
That should put you close enough that timing isn't an issue, and then you can dial it in with a timing light later on.
I re-timed the CAS to be sure and checked fuel pressure. I plugged a gauge into the end of the pressure line before the filter, the fsm says that with the pump running the minimum is 90psi in getting around 50 so it must be time for a new fuel pump. Notes: 50 psi is a lot so when you think you’re just going to pull the gauge out a little and let it drip think again. It’s after filter in this picture but before the filter is the same I checked it. After about 7 minutes off.
You vs the guy she tells you not to worry about
Don’t recommend the carter fuel pump from rock auto, doesn’t use the factory connector and I don’t really wanna hack up my sender unit to make it fit. I think it’s the sock it’s really gummed up, I’m going to have to take it off and recheck fuel pressure.
The sock was definitely part of the problem, if I put the gauge straight on the pump, I get 70 psi really quick. The issue im having now is that it seems to be leaking out of the o ring on top of the pump since I only have 60 psi when the pump is installed. Has anybody ever tracked down one of these for less than the 45 dollars Mazda sells them for? Atkins sells one for a Miata that looks really similar but they also sell one for a third gen that looks similar too???? Im going to keep looking for now, $45 is a lot for that little thing, might go to NAPA and see what they have. The car might run on 60, if I get a chance ill try it tomorrow. Autozone part numbers for factory plugs, I just ordered new ones the old ones don't look great. EDIT: I re-read everyones advice to make sure I checked everything mentioned and realized that my phone was autocorrecting the whole time and putting the little boxes in, sorry about that.
EDIT2: The part number is the same for the FD one(BP0213ZE5), I see 41 dollar kits that come with pump sock and o-ring so they definitely exist nobody sells them though.
Double check those plugs when they come in. Copper isn't necessarily a problem, but Rx7 spark plugs have a unique shape with four pie cuts around a straight center electrode. BR7EQ leading, BR9EQ trailing. Those Napa parts may be correct, but verify before installing.
Hopefully you can find an o-ring for less than $45.
The sock was definitely part of the problem, if I put the gauge straight on the pump, I get 70 psi really quick. The issue im having now is that it seems to be leaking out of the o ring on top of the pump since I only have 60 psi when the pump is installed. Has anybody ever tracked down one of these for less than the 45 dollars Mazda sells them for?
Really; $45? Are you talking about the O Ring at the end of the fuel pump that goes into the tapered shaft of the fuel pump sender?
12-06-22, 07:52 AM
1000% it can never get clean, Maybe because I hadn’t started working on the car in that picture. I will say I am very fortunate to have the shop space I do.
. So according to the internet for the voltage drop to occur the other end needs to be connected to something, so im guessing to get the FSM spec is for probing the connector when its connected ill try it later. My next guess is fuel pressure maybe, I can hear fuel flowing when the pump is on but I don't know if the regulator is just passing it all over.
