kartoshka

I have a good one for you. My car stumbles when I accelerate heavy.
I did:
1. Rebuild engine.
2. New spark plugs
3. New Wires.
4. New distributor cap.
5. Checked MAF sensor ( workes good)
6. Adjusted the timing.
7. Checked EGR valve ( seems to be working good).
8. New air filter, new fuel filter.
9. Checked temperature sensor ( works good)
10. Checked for vacuum leaks.
11. Computer code 55.

The only thing I'm thinking of, is timing advance on distributor, however I didn't check it yet.
Fuel injector is OK, because after 30 min of driving, engine works fine.

What else could it be?

Thanks for everyones feedback.

 

MagicPie

Most likely a leak in the intake manifold (if not timing) since you did rebuild the engine am assume the intake manifold was tooken off then back on maybe not a good seal or someting around that area

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96 200sx with Erebuni 285 kit (GTR), 17" OZ superleggras, wilwood 4 pot 11" brakes, rear disc conversion ,lots suspension upgrades, hotshot header, stromung exhaust, CAI, UR pulley, JWT cams and ecu, racing seats, new carpet and rear seats a few other cosmetics sold car for 350Z

MagicPie

or the emissons stuff

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96 200sx with Erebuni 285 kit (GTR), 17" OZ superleggras, wilwood 4 pot 11" brakes, rear disc conversion ,lots suspension upgrades, hotshot header, stromung exhaust, CAI, UR pulley, JWT cams and ecu, racing seats, new carpet and rear seats a few other cosmetics sold car for 350Z

kartoshka

It could be. I'm going to change the intake gasket on Saturday, may be it will help.
Thanks for input.

James

when you say rebuild engine, can you list what you did?

code 55 means all functions operating normal.

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05 Frontier SE CC 4x4 (6spd)
Manual Swap Parts!!! Magnaflow Muffer For Sale

 

psuLemon

what bout your fuel pump... did you check that...

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MagicPie

Its true code 55 means everything is okay but theres really nothing to tell the computer your intake manifold has a leak and its possible that the fuel pump may have a problem but kartoshka I would check the intake manifold for a leak I once broke a bolt that bolts the intake manifold the bolts missing head was enough to cause a small leak that gave me some problems so the leaks needs not to be very big

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96 200sx with Erebuni 285 kit (GTR), 17" OZ superleggras, wilwood 4 pot 11" brakes, rear disc conversion ,lots suspension upgrades, hotshot header, stromung exhaust, CAI, UR pulley, JWT cams and ecu, racing seats, new carpet and rear seats a few other cosmetics sold car for 350Z

kartoshka

James. Rebuild engine

New piston rings, new bearings, i installed brand new head, all new gaskets, seals, new oil pump. Just like the book says.
I really believe it could be a intake leak. Fuel pump? I don't think so because when the car is hot, it runs fine. However to get to the point when the car is hot you need to drive for 20 minutes, I don't travel that far.
Another thing I'm thinking it could be is the distributor, but I'll check intake first. MagicPie I appreciate you feedback I'll let you know what happens next.
\

Thanks

jer28

Verify that the rotor is pointing to the number 1 wire at tdc for cyl number one. This can be done by removing the dist cap as you probally know.

kartoshka

Yes, rotor does point to the right cylinder. How in the world it would work?
I set the ignition with timing light too.
Thanks anyway for trying to help out.

 

MagicPie

Did you fix your car? YET

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96 200sx with Erebuni 285 kit (GTR), 17" OZ superleggras, wilwood 4 pot 11" brakes, rear disc conversion ,lots suspension upgrades, hotshot header, stromung exhaust, CAI, UR pulley, JWT cams and ecu, racing seats, new carpet and rear seats a few other cosmetics sold car for 350Z

Nico Flax

I had to have an engine swapped after I blew up my old one, and seem to have the exact same problem, only it doesn't go away after 20 mins of driving, one thing I did notice though was fooling around with the distributor made a big difference. Does yours almost feel like a misfire? Like two or three soft blips from the engine before it takes off? I never thought of an intake leak... guess I'll have something to do this weekend!

kartoshka

NO haven't fix the car yet. I'm working on my Pontiac right now changing the transmission. Tomorrow I'm planning on spending some time on my Nissan. I'll keep you posted guys

kartoshka

OK Finnaly fixed the car.
The problem was intake leak. I was lazy when I was installing new gasket, and didn't clean surface really well, didn't apply silicone, therefore I had to pay the price and fix it second time.
This time I cleaned the whole throttle body, ISS valve, put new gasket and silicone where monifold is. Looks like now the car got additional 20% power, no stumbling anymore, better gas milage.
OH, I forgot to mention, my car stopped annoying whistling too. This whistling made me think that there was a leak in monifold, plus MagicPie helped me out here a bit, by telling me what could be wrong.

Anyway, thanks everyone for help. If you guys need any suggestion let me know.

jer28

How did you go about finding the leak? Did you just spray starter fluid when it was running or did you pressurize the intake?