Monday, December 29, 2014 - 09:52 pm, by: Patrick Fenis(Soarer_beast)
Hi forum buddies! Unfortunately i have an issue. I've searched forums but nothing really seems to click.
I have a 1991 v8 with EMV: uzz31.
From a stop, when i put my foot down 1st gear is sluggish. When i reach 5800-6000rpm in any gear the car dies, almost like it 'stalls' and loses all engine power or something. When it backs down to around 5500rpm again it drives like normal.
it's sluggish when cold and worse when warm.
Car drives very smooth, but if you floor it, it's a bit sluggish, and once you hit 6000rpm the car dies. 2 seconds later it comes back to life.
idle speed is 650-700rpm in drive. In park idle sits at 1000rpm, but sometimes sits at 900 or 800rpm.
Could this be a misaligned TPS? Will a badly aligned tps cause sluggish first gear?
I had to change it a while back, but didn't use a feeler or multi. I just took old one off, put new one on. Adjusted by hand til idle was at 700rpm.
I really have no idea what it is, the plugs looked ok last month, Soarer has no leaks or drips. IACV was apparently cleaned before purchase, no idea about the ECU condition, but there are no error codes on the EMV or dash.
To recap. From a stop, if i put the foot down (pushing button under pedal) in 1st gear, the car slowly and smoothly gains RPM, will not spin wheels, and has lack of speed til around 30kmh, then it takes off like usual. in second gear, putting the foot down in normal mode(pwr off), does not kick back to 1st sometimes. Keeping the foot down will 'stall' the car at 6000rpm, til it backs off to 5500rpm or so and comes back to life.
Car is taking about 8-9 seconds to reach 100kmh. Car will still reach max speed, it's just sluggish in first or when you need INSTANT power. help would be appreciated
Tuesday, December 30, 2014 - 03:18 pm, by: Rob Charles(Pearl_white)
Hi Pat, I seem to be having similar issues.
Slow acceleration in first - and no instant power when you put the foot down.
I've tried everything under the sun to fix it, aside from oxygen sensors, new fuel pump, and an ECU recap.
I suggest an ECU recap first. I myself am due for a recap in Jan - so will let you know how I went. This is basically the cheapest fix which MAY fix your problem. I posted a thread where you can find an ECU recapper for $75 bucks in Vic.
ECU's in these cars last about 10-13 years. The 1991 would be long overdue for a recap if not already done. It costs around 3 cents per cap.
If you can solder, a tip which i read would be to cut the old caps off and simply solder new caps to the old legs - this prevents further issues with tracks and so on, if goop has leaked as I understand. This only works if the legs are still fine obviously.
(Me personally, I hate soldering so will be getting the soarer guru to do it for me )
- If the car is running fine , not overheating, no smoke, no this or that - and you've checked fuel filter/air filter/tranny - it HAS to be the ECU. That's really the only logical thing left. Or a vacuum leak.
Monday, January 05, 2015 - 07:15 pm, by: Patrick Fenis(Soarer_beast)
Hi! ive been a bit busy but sort of have news.
I had a fiddle with the Throttle position sensor and my revs seem more perky. I dont have trc errors so that's lucky!
Im going to replace fuel filter and ecu over weekend and hope for the best.
and rob, thanks for advice! Ive seen a lot of your posts now, you know what you're talking about (Usually... lol) Im going to call that ecu guy if the fuel filter doesnt fix it.
I changed pcv valve already. Changed air filter too, and no change.
oh, the stalling at higher revs stopped after fiddling with the TPS a little also.
oh, my power steering fluid isnt leaking but i have to fill it up a bit every month. only 30ml or so. Well, i guess it is leaking then... but you cant see it anywhere.
Wednesday, January 07, 2015 - 03:03 pm, by: Rob Charles(Pearl_white)
That's what happened to me.
Power steering fluid was leaking from pressure switch(idle valve) on power steering pump, sucking fluid straight into the intake - and causing a vacuum leak which made the car surge in park, and have an idle speed of 1100rpm in drive.