Fuel Delivery Maybe?

[~laser_craver~]

Alright, i just dropped a new motor in my car 80k miles good compression etc etc. And i start it up and it rns rough sounds and seems like running on 3 cylinders to me. But when reved up or i get on it it seems to get all the cylinders going. Also i can get on it almost 1/2 throttle and itll build 10psi and start pulling really really hard then all of a sudden it hits like a wall..... Just BOOM and slows down. The fuel thats in the car is relaly old so i was thinking that might have something to do with it.... Anyone please help i wanna get this thing running smoothly And on my maf i installed i read in a tech article the white wire needs an rpm source and he recommended that i use the small blacke wire coming off the cas (cam angle sensor), but there is 2 black wires and i wasnt sure what one to use could this be part of my problem?

 

[Old Mitsu Tech]

First, talk to FemmeDsm. She had fuel tank issues. She would be the fuel tank expert at this point.

Secondly, the latter sounds like fuel or boost cut, especially if it's rather violent.

You could have a stopped up fuel filter or such.

If you are dropping a cylinder, you need to isolate that cylinder as whether it's losing fire or fuel. You can do this easily by simply squirting some carb spray in the intake while it's missing and if it picks up and smooths out you have a vacuum leak or fuel problem. If it doesn't change, it's electrical of mechanical.

Let us know.
Good Luck

 

[femmeDSM]

.... ^^^^^ So true, so true!

First of all, having had (recent) first hand experience with old gas, you need to drain that tank and fill it with some good gas. I would also recommend half a bottle of Seafoam or another similar cleaner added to the tank, as well. This will clean out all the moisture from the tank that could be causing the hard starts/crappy idle.

The "hitting a wall" symptom you are experiencing sounds like fuel cut to me, too. Have you performed the obvious tests (boost leak, fuel pressure, etc)? Are you getting a CEL? Is the car hard to start at first (maybe sounds like a misfire, will die a couple times, then start)? If so, you could be looking at a fuel pressure issue, or a faulty coolant temp sensor. I didn't check your mods list, have you installed an aftermarket fuel pump? If so (and even if not, really), check the O-ring. It can cause a lot of weird starting problems that mimic more serious issues.

Good luck. Let us know what else is going on (i.e. the questions I mentioned), and we can go from there.

 

[98eclipseRS]

Just like everyone has stated do a boost leak test and drain the gas, or don't boost on the tank until it is finished and you have new gas in the car. It really sounds like you are having a fuel cut issue do to a boost leak so the car is seeing to much air. Fuel cut happens because the car is seeing to much air, not becuase it is seeing to little fuel. As for the MAF/T the white wire gets tapped into the larger wire of the two. On my 2g they were grey and there was a deffinate size differance between the two. Use the larger one for your rpm signal.

 

[Talesin]

The 90 CAS have all wires the same size. They're a bit of a PITA... especially when your mechanic snips them to resolder, and doesn't do it one at a time. :b