Not starting after engine replacement

[ninetyone300zxTT]

I'm on the tail end of an engine replacement in my 91 TT, but I'm unable to get the car started. The engine will spin over, fuel pump runs, no error codes, has spark (although CAS had to be swapped from the original to the replacement), and I verified that the injector and spark connectors are on the proper cylinders. When I pulled the CAS out and turned it manually, I could hear the injectors, and I could see spark on the plug I pulled to make sure the PTU was functioning properly. The tach is also showing some movement when spinning the engine over.

I bought this with a locked up engine, so I've never heard it run, but I assume it did before the engine locked up. This was apparently a newer engine, so I had to swap the intake, CAS, and use the new injector plugs. I also had an ignition code with the replacement engine's PTU. Once I swapped back to the original engine's PTU, the code went away.

As far as I can tell, it should at least start and idle, or try to cough to life, but all I get is spinning and smell of fuel.

Where are some places I should start looking? Also there is a 4 pin square connector on the passenger side that I'm unsure where it plugs in.

[lexcrob]

Spray a small amount of starting fluid. Give her a bump if she runs for a second you have spark and mechanical timing is close at least. (don't spray in half a can and burn the car down) Normally it says on the can 2 seconds or whatever. Keep the fire ext. near by.

If that doesn't work do a compression test. Far as I read that's only thing you missed. Could be something like the lifters holding all the valves open like just happened to me the other day. Talk about a head basher.

Spark fuel compression timing and the correct amount of all that its that easy keep it simple.

You got it!
Rob

[ninetyone300zxTT]

I'm smelling fuel (exhaust is off right now), and the plugs are wet.

[ninetyone300zxTT]

Alright, making some progress but seeing some weirdness.

I checked the codes again, and I'm getting codes 11, 21, and 35 (it's not plugged in, not worried about it yet).

When I take off the CAS and turn it slowly though, I'm hearing the fuel injectors, and I get spark with a pulled coil pack and spark plug. Wouldn't both of those seem to indicate good working parts? I've also used two different series 2 PTUs with similar results (sometimes, rarely the engine will pop once after I let the key go from the start position). Having two bad newer style PTUs is pretty uncommon isn't it?

[nissanfreak12]

Are you sure the connectors are not corroded? Green "crud" plagues early z's and can cause the sensor to not work right or at all.

[vereshchak]

Code 11 means that your crank angle sensor circuit is faulting. Crank angle sensor could possibly be what is restricting your engine from actually firing up. You'll still be able to free spin the engine but you won't be getting the right signals for fuel and spark. You say that you have spark and have ignition (despite your codes are shooting hints that it may be ignition) so if you definitely have spark and you definitely have fuel then you have to check air ways. Having your intake or exhaust clogged will give you similar effects.

I agree with nissanfreak, Follow the codes with a wire brush and a can of electrical cleaner and clean every and any connector especially those correlating to the codes. My TT used to get me to where ever I needed to go and when it was time to go home it would barely crank sometimes leaving me SOL. I clean all my PTU connectors and I've never had that problem anymore

[DCaff300ZX]

Agreed with vereshchak and nissanfreak, before anything else a green crud run will be needed for ALL engine connectors concentrating on PTU harness, IACV, CTS, injectors, and CAS. Your Z will toss a ton of bogus codes at you due to corrosion.

[ninetyone300zxTT]

Sounds good, I'll run through and clean out all the connectors tonight and let you know where things are at afterwards.

[ninetyone300zxTT]

It still didn't start after cleaning out all the connectors. What did fix the issue though was another PTU. Not sure why the other two aren't working properly, but at least it started. Now I can work on putting it back together completely

[nissanfreak12]

If that is the case, check the back of the plenum and make sure all the grounds are connected. There is one by cylinder 5 runner tube that should be attached, if that is not attached it is known to fry PTU's

[ninetyone300zxTT]

It is, and has been for a bit. But it may not have been the first time I tried starting it.