thetwood

Yellow and black with spade seems close enough...

Ha. Sorry. Wrong picture. I should have just read a book instead of working on the car tonight. Too long of day...

I'm getting things put back together now. Injectors with new gaskets are in. Put the new fuel regulator in. Took out the in-line fuel filter before the fuel pump so it's unobstructed (it had some debris but not a lot and seemed okay, but one less thing that could cause low pressure). New gasket and valve cover replaced. Before trying to start up, I was going to disconnect the starter and see what the fuel pressure looks like just with the fuel pump going. My question is, which wire should I disconnect from the starter? I could just disconnect all of them, but thought I'd ask for advice.

Should be getting injectors back this weekend. In prepping, I realized the EFI hose currently in the car is 3/8" instead of 8mm or 5/16". I can get some 5/16" and change it over. Would having too large of a fuel hose cause drop in pressure?

My son is really looking forward to getting the injectors back so we can put things back together and keep working. I've been trying to keep from changing too many things at once. Every time I do that I don't know which change caused which effect.

A bit of information coming in. I don't have the full results, but heard from the company I sent my fuel injectors to for cleaning/flow testing. Results were that the flow rate was approx. 190cc, which is pretty close to the 185cc of original. They should be on their way back to me tomorrow and I'll look at the full results. I'm assuming with this news, I should go ahead and reinstall vs purchasing new ones. Also purchased a fuel regulator that I'll put on at the same time, in place of the aftermarket there now. With both back in place, I can start looking at why the fuel pressure is so low.

Thanks @Zed Head. Given what you're saying, it doesn't sound like the cam is of utmost concern at this point and I should concentrate on other areas. I'm going to order a Fuel Pressure Regulator, test some of the other things you guys have pointed me to and wait for the results of having the injectors flow tested.

Measured cams. 33.3 mm short, 40.3 mm long. At least really close to that, converting my inches (long converted to 40.386 mm). Seems to be really close to stock if not stock. PO claims it was swapped out, but the lift doesn't seem to match up to any of the Schneider cams (at least those available now) which all have a much larger lift... Raw numbers: Short: 1.31" (33.274mm) Long: 1.59" (40.386mm)

Got it. Know I have those, just need to figure out where it put them in my garage... Thanks. Appreciate the help.

I was looking at the OE FPR and have a question. With the fuel rail that I have it doesn't look much like the pictures in the EFI book. It's basically tank > fuel filter > Rail (injectors) > return > FPR > back into tank. Maybe not too much different than stock rail, but less loops and such. If I get a stock FPR, do I just put it on the return line after it's gone through the aftermarket rail?

I'm new enough to all of this that I'm not sure what exactly I'm supposed to measure here. Advice on where to read/learn more so I know what I'm doing?

Injectors are off to be flow tested, so type/flow can be nailed down. Not sure what the full turn time will be, but expecting a few weeks with shipping in each direction. I'm a bit nervous about pulling the camshaft after the warnings. I don't mind digging into things, but would prefer to not need to pull the fan, etc. I have the time to do this as I'm waiting for the injectors, but sounds like it may make sense to test other things first. But do appreciate all the help with the tension retainer. I'm going to go ahead and cut one out now to have and test. Per @Dave WM, I'll read up on how to test the ECU and temp sensor. Also still working on tracking down some parts to go back closer to original like the charcoal canister.

I do not in fact have a fax machine... But if you can email it to me that would be awesome. I have plenty of hardwood scrap here, so could cut one out easy enough.

The angle of the picture doesn't help. Originally, it actually was on the return side. That didn't seem right, so I switched it to the feed. It's inline with the filter now, just doesn't look like it in that picture.

Question for everyone. How do I identify the model/type of cam? Pulled the valve cover, but the camshaft is just labeled Japan and C on one side, and E30 on the other. The C is on it's own raised section on the shaft. To fully identify, would I need to pull the camshaft? If so, I have a bit of research to do as I've never done so.

Will figure out how to get the exact model/type cam. And thanks to everyone for setting me straight on the AFM. When it didn't look like the pics and with all the stuff from JEGS PO had ordered, my mind just saw that vs JECS... Need to pay more attention...

Going to leave the AFM alone for now. Planning on going through the fuel injection system and testing everything we can, testing vacuum, etc. Did fine out a few more pieces of info. Haven't verified, but PO says the injectors should be original type, not turbo (we'll see). He did change out the throttle body, as many had observed. He also switched the cam to a Schnieder Racing Cam. I'm not sure exactly what that does or will mean, but one more piece of the puzzle. My son turned 16 two days ago, so he wanted to get up early and go to Cars and Coffee. Gratuitous pic of him (the one with long hair) next to his car. He had a blast and we had a lot of people stopping to talk. Everyone had one or knew someone who did and have fond memories. Was fun.

Have been reading through the AFM documentation, then went to the car. The AFM is not original. It's from JEGS. I can't find anything on their site with the model number on it (A31-625 000), but it seems to be listed for an L28 and there's some faded marker on the body that looks like it says 280ZX. The cover was sealed, but popped with a bit of a pry from a screwdriver. Inside, it doesn't look exactly like what's in the documentation but is close enough to work on. Glue blob is intact and I can't see where it's been adjusted. I'll go through it in much more detail, but just doing the quick fingering check, moving more than about a tooth in either direction did bad things to idle. I'll dig into the tests and go through the other suggested checks from the document when I get more time.

Haven't made a lot of progress yet. Still planning on pulling the injectors to have them flow tested, but haven't done so yet. It was my son's 16th birthday yesterday and he wants to drive his Z to the local Cars and Coffee this Saturday. We go a lot, but he's never gotten to take his own car. Seems like a worthwhile reason to wait a few extra days... But I did receive a fuel gauge from Amazon yesterday. Put it in place of the Jegs inline fuel gauge and tested again. Got similar readings as before, and nowhere near 36. With the Begi fuel regulator hooked up, it sat at 10 psi. With not vacuum to it, fuel pressure was 16. Will send off the injectors this weekend and hopefully get some answers on that next week. But fuel pressure doesn't seem nearly what it should be.

That would be great if you could. I don't mind continuing to get closer to stock, but it's going to take a lot of searching for parts, tracking things down and cost of course. If I can continue using things we already have that helps... My first goal is to pass emissions. Doing so allows my son to drive to school and back and buys us time to make additional changes.

OK. Here's my current plan after getting all of this advice: 1) I have a new fuel pressure gauge on the way. Confirm what the pressure really is. 2) I'm going to remove the fuel injectors and send them to be flow tested/cleaned. Figure out what I actually have. 3) I'm working on getting a charcoal canister and bracket. You were right, the new non-venting gas cap caused a vacuum in the gas tank without one. Trying to decide how much else to change out. Should I switch back to a stock fuel rail while I already have the injectors out? that way I can add cold start back into the system? May take me a while to get through this part, but I'm sure I'll have more questions once I get through some of this...

Suggestions on where to go to get them tested?

Does it make sense to change the injectors to oem? Or do I need to figure out what else was done to the engine first?

I understand. I'm walking into an area where you all have great experience and I'm the nub. I'm bound to get overwhelmed till I at least start to catch up. Not a problem.

I can'd fine any numbers or markings on the injectors top or bottom...