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Hi guys, new to this car and am really happy with the car, its a 1991 Nissan 200sx with a near enough stock CA18, has intercooler, air filter and 3 inch turbo back exhaust. Now it smells ridiculously strong of fuel both inside and outside the car. If I'm driving and plant my foot it seems to stutter and backfire but if I hold it halfway down it boosts absolutely fine and pulls really strong. Anyone have any ideas?
Check to see if the lid has been off the tank. If it has, they probably didn't replace the seal which swells and doesn't fit once the lid has been off
If the fuel pump hasn't been replaced then it probably needs replacing by now.
If it has been replaced, check for a split in the hose that runs up the side of the pump as this leads to low pressure.
Have a look to see if it had a carbon canister that has been deleted incorrectly. There are plenty of posts on here about how to do it .
Also, get a compression check done to eliminate problems with the valves.
Hi, thanks for the reply. I have a manual fuel pump switch in the car so I assume it has a new fuel pump but I will check this. If I just have half throttle the car boosts really well and has absolutely no issues at all, it's only On WOT that I have the issue.
Don't forget any original hose is 25/30 years old and could well have perished (which is why I've spent a whole day putting stupid purple hoses on an engine).
Clogged fuel filters can cause the exact issue you're describing. Haven't seen it first hand on these engines but I have on other stuff, worth a check. Although if you're smelling fuel outside of the car too it sounds like a leak is the issue.
Boost leak - smoke test.
Idle switch setting - mode IV ecu test.
Fuel pressure, remove vac from FPR and take it for a drive. If improved fit a pressure gauge on a T between filter and fuel rail and cable tie the gauge to the wiper, go drive.
Check idle mixture, if you have a lambda, mode II ecu test up to 3200 rpm. Red/Green LED should flash in sync 9 times in 10 sec at 2000 rpm. If it fails, is out of sync at any time or has delay before it starts to flash when opening the throttle most likely a boost leak.
ECU test mode Mode III and dynamic Mode V (while driving)
Turbo compressor oil leak, check the duct work for oil and watch in mirror for smoke. At high airflow it picks up more oil and fouls the plugs. Hotter plug may help, if its on 7's switch back to stock 6's.
If you have a lambda unplug it, go drive to see if improved. Remove lambda test with propane torch and voltmeter, if OK it's a boost leak.
As JackB and Jonny say the fuel smell means you have a leak. I've had to cable tie rubber hose to old metal line the whole way from engine bay to tank on 2 cars as the pipes rot near back axle.
It's only when the car is running thst it smells, when it's off there's no smell whatsoever, and theres no evidence of any residue on the floor when running?
Check top of inlet manifold for injector fuel rail seal leaks.