a host of issues

[fixkick]

Thank you and Happy New Years to you as well.

I am going to just go right back down the list.
My X90 does have an automatic transmission with the original ECU.

My gas mileage has dropped by half (around 10 miles a gallon). (limphome in effect, CEL glows running?) or real high fuel pressure, or leaking injectors.)

Yes the CEL glows running. (sorry sure it is , DTC set.

I noticed the the fuel pump is running all the time (not just a few seconds after the key is turned). that is ECU going nuts. it only runs 3 seconds, key on , only. (never heard any 96 doing this) no G16B.

Sorry, just so I am clear when the key is in the off position the fuel pump is not running. But when the key is on you can hear the fuel pump running. If I had the key turned on for 20 seconds the fuel pump will run the entire time. You can also hear it in the fuel pressure regulator. I did swap out the fuel pump relay with the main ECU relay (10 minutes ago) and the fuel pump still runs when key is on. that is real bad, did the pump stop running with relay pulled key on
yes, ECU has gone nuts, no , the pump has been hot wired, by grimlens. a very dangerous ECU. to drrve.

When I checked the spark plugs I noticed that the number 4 boot that goes down onto the spark plug has a hole in the side of it. (new wire set)_ this will set P0304 only.

I went and bought a brand new set of plug wires and they are now installed.

The brakes. Some times I have great pedal and other times it goes down so low that it will scare you. Master cylinder seems to be on way out. did engine rpm drop very low, as brakes acted funny, low means below 800RPM?
pedal effort or pedal distance down? did pumping the brakes , fix this fast.? that is gain a high hard pedal>?

I didn't notice and drop in RPMs when I applied the brake (but I will make sure to look for this next time). The pedal distance down, very close to the floor before the brakes started to stop. But you are correct pumping the brakes brought it back to "regular pedal" for a little bit.
MC is heading south , im sure its not the booster, sounds like rear front section of MC is leaking down and only have rear brakes.

I did check all of the grounds on your "critical grounds" page. No signs of corrosion and all are tight. VG



So if I am thinking correctly brakes, starter and parking switch (are a problem) but are not related to any of the engine issues.
the parking errors to ECU will cause it to inject fuel as though not cranking. and may be weak fueling cranking on cold days.
the ecu sees you crank and works very hard to keep injection working good, as battery voltage falls....
but yours is showing parked while driving... my guess is the PRNLD switch is intermittent.

but right, these errors are not making 300s or 340s.


I am going go start it up and check to make sure i have 13.3v to 15v at all time running, no 12v power loss to ECU or DIZZy
no corroded ECU fuses (there are 3 fuses).
Then I will drive it around the block to get to operating temp and check the compression on the #1 cylinder. If it is at 170 (WOT) or about no need to check the rest? Correct? if the #1 is high that means the timing belt didnt slip, or not by much,if so.... usually it drops to 80, with belt slip....
if #1 is low then i check all 4, if all 4 low the belt has slipped. (do it wide open throttle, 75% or more.. to get bench mark readings.
check them all, my reason for #1 is its close, and if reads 80psi , in 5min test, its really good to know fast. if it reads good, i still read them all.
but belt slip is so common. if you see them all low, the ignition timing will be way off unless someone reset it to track the lies of the cam (bad)
If good then I can check the spark timing ( I have a timing light and a beat up timing cover).


Should I clear the codes now? Or just leave them be until I figure more stuff out.
yes clear them and see how many come back.
keep in find, moving parts around , on engine can trip codes, key one. the ECU does many monitors, all time key on , running or not.[/color




Again thank you for your help.

[color=#FF0000]your fuel pump scares me. never seen that ever. unless hacked.
one guy , did, one time hot wire the FP relay and burned the ECU FP relay transistor to a crisp and it shorted, and pump ran full time.
may persons do this hot wiring because of this false belief that pumps run full time. they do not. (but yes running engine and spark good)
hot wiring is very popular with some, the guy that did that used a paper clip and landed on the wrong pins. BOOM let the smoke out.


cheers.