91 300zx tt no start, has spark and fuel

[edj3663]

Hi guys, I'm new to this forum and this car. I've had it for 6 days tomorrow and like the title says it won't fire. I did a fuel pressure test and it came up with 43psi, I pulled 2 coils and plugs and it had good spark plus fuel shot out at me from the cylinder. Me and a couple buddies tested the tps and the hard idle sensor or whatever it's called and they tested good. Did a code test on the ecu and it came up 55, so nothing there. I can't see any intercooler lines off and the maf doesn't appear to be too dirty. The problem started when I was leaving my dirveway, I left hit second then all of the sudden it started sputtering and lost all power and stalled. I pulled over and it would fire briefly but run like complete s***. Now it won't start at all, won't even try. I think it might be some little sensor I just need some guidance. I know carbed v8's and I bought this to learn about them and boy am I getting a lesson lol I'm used to fuel plus spark equal go.

[Ziggy1621]

I'd start by testing the crank angle sensor. If you turn it by hand, you should here the fuel injectors firing one at a time.

A similar thread cas-problem-t472155.html

[nissanfreak12]

Test all the injectors, being a 91, those style injectors fail sometimes with out warning. Use an ohm meter and they should read between 10-14 ohms. If they are any higher, they need to be replaced. Check all six.

When was the last time the timing belt was replaced?

[edj3663]

Alright I'll go give those a try. Also is there a way to identify injectors on these cars? The wires running to the injectors are all spliced together with butt connectors so it makes me think they aren't factory. Also I'm not sure about the timing belt.

[noZa]

This happened to me last Sunday. I know you ran the codes but it's worth a shot. Check your coolant temp sensor which is located on the front of the engine. It has a yellow connector. Mine shorted out and was telling the computer that the coolant was at 360 degrees. Replaced and it fires right up. Although now its running really rough.

[edj3663]

All of the injectors were between 11.3 and 11.5 ohms so no problem there. I'm trying to take the CAS off to spin it, I took the bolts out but I'm worried I'll have to re-time after I take it off. Can you spin it without taking those bolts out?

[edj3663]

I had someone crank it and you can hear the injectors clicking. If I just crank it, it will hit once or twice every now and then. This is frustrating. What would all of the sudden go out after it sat warmed up for 10 minutes as soon as I take it on the road?

[nissanfreak12]

Check the belt, if your getting spark, fuel and air, the only thing missing is timing. If you pull the driver timing cover you can see the condition of the belt. See if it has slack in it. If it has slack either the belt broke, a pulley gave out or the tensioner failed. What you need the car to fire up is ecu, ptu, cas, injectors, coils and plug. Those actually make the car run, it will run like crap, but run. Check the belt.

Also like mentioned earlier, take out the CAS and check things that way, will make life a lot easier than having someone crank over and try and listen to the injectors. If you mark were you had it, you won't have to re-time the car.

[edj3663]

Alrighty, I'll check that this afternoon. If I do have to do a timing belt should I just go ahead with the 120k kit? I'm not sure when it was done last. The car did come with a thermostat and supposedly the motor on has a little over 5k on it. I have no way to confirm that though.

[t.mcginley.jr]

If you don't know which one was last done, do the 120k service so that you replace all the idlers and stuff too. You should also replace the idler studs as they have been known to break

[edj3663]

Alrighty, any recommendation on kits? I found one on conceptzperformance.com that uses all Nissan oem parts and it's 550. I don't want to break the bank but I'm not scared of spending the money to get good parts. While I'm in there should I do the cam seals? They don't leak now but it would suck if they did right after I get it all back together.

[Ziggy1621]

Call Harry at Ztuner http://www.ztuner.com. I bought all my stuff from him. His prices are very competitive, and I like speaking to someone about tedious stuff like this rather than just clicking 'add to cart'. Tell him David sent you

[edj3663]

Thanks dude! I'll be sure to do that. And how do I get that stupid cas off? I've been hitting the sides with a screwdriver and mallot, I have like an eight inch gap around it but it will not come off. Plus I'm afraid of hitting too hard and breaking it.

[Ziggy1621]

Don't hit it! It's electronics three 10mm bolts on front and it comes right off. Just the center comes off. The bracket is bolted behind the timing cover. Leave that on.

Post a pic of what you have so far... It doesn't have 8" of movement

[edj3663]

Never mind, I got it. Just took some light persuading. Also that was supposed to eighth, not eight lol I spun the shaft and I could hear everything clicking and buzzing when I did it, it also made an exhaust note once when I first started doing it. I also pulled my driver side timing belt cover and I'm not seeing much for timing marks. Are they clearly defined? and what color? I'm seeing yellow and white markings on the cam pulleys.

[Ziggy1621]

Yes, they'd be evident

[edj3663]

Ok, also how much play should there be in the belt?

[edj3663]

The dimples line up on both of the cam gears I can see... I'm stumped here. One of my buddy's who has a leakdown tester is gonna come over and we're gonna look for leaks in my turbo lines but damn I'm lost... Also I didn't make a mark on the shaft of the cas before I spun it, I marked the mount lined up with the cam covers and then I made a mark on now what I realize is the bearing in the cas so no good mark there, so is it all of wack now?

[Ziggy1621]

The FSM gives the specs on the belt: http://www.nicoclub.com/FSM/300zx/


You will have to set the cas. Scroll down to "ignition timing" in this link everything-you-need-to-know-about-the-z32-t508376.html

[edj3663]

Well I put it all back together and when I crank it now it will try to fire, just won't quite go. It seems to help if I play with throttle when cranking. Me and a buddy pulled the plugs and burned the ends clean and that helped some. Also when I was cranking it smoke would start coming from the engine bay and when I pulled the plugs a lot of smoke came out of the middle cylinder on the drivers side.

[theSLOWz]

Are you sure you have good spark? Did you test your PTU? I'm thinking if it has spark, fuel, and timing is good, it should fire... If you crank and crank it then pull plugs what do they look like? soaked with gas or dry?

[edj3663]

I didn't test my ptu cause if I'm getting spark it should be good right? And I'm right there with ya, in theory it should fire, just won't. And when I pull the plugs they are soaked in gas so it's getting fuel.

[nissanfreak12]

How good of a spark is it getting? Which plugs did you pull? All six?

[edj3663]

It looks like a healthy spark but I will still test my ptu today just to be sure. And yeah I pulled all six. I just bought some new plugs and a compression tester so I'm gonna go play with that now.

[edj3663]

Compression tested well, all between 170 and 185 except for one that was 150. Not good but not bad enough to make it not run. I'm trying to test my ptu right now and I'm not having any luck. When I test for voltage on either side of the ptu I get nothing, I still have spark though... I have the key on, so I guess I'm not doing something right.

[t.mcginley.jr]

You might want to try swapping in a known good one just to be sure. How are you testing for voltage?

[edj3663]

Tomorrow I'm going to call Nissan to see if I can get a new ptu on recall since it's the old style. And I had my key on, the negative prong on my meter on the batteries negative post and touching the connector prongs on the ptu. I pulled it off a did continuity test and one read less than all the others. So hopefully I'm on to something with this.

[t.mcginley.jr]

Didn't realize that you had an old style PTU. That's definitely your problem then, I'm surprised it even lasted that long

[edj3663]

Man I hope that's the case. I ordered one from czp cause Nissan wouldn't honor the recall and I'm gonna solder in the sub harness connectors and relocate it too. Don't know if I'll go under the nose piece or not, I don't like how the wires go right next to the radiator.

[t.mcginley.jr]

Yeah its a good idea to relocate it, the main reason they fail is from heat damage