My subaru is lacking power. changed the plugs, rotor, cap, fuel filter. Started and ran fine but lacked power until about 4000 rpm. parked it. the next day it starts but barely runs. It's a TBI model. Fuel pump? Didn't change the plug wires, should I do that? Seemed to run better at half throttle than full throttle. don't have a lot money to start replacing everything. Any suggestions?

Thanks

if it runs it wouldnt be a fuel pump, i dont think anyway. is it carb or TB? if carbed its most likely that. if its the carb do a webber carb. my 1987 GL is carbed and sometimes it will shutter or lack power at cold temps and if i gun the throttle. saving for the webber...

 

gonna leave the top part incase its carbed. not sure what TBI means. but if its throttle body then it has to be a sensor at the TB or a O2 sensor. melted cat or something.

 

hope that helped any.

 

87roo.

Edited March 19, 201115 yr by 87roo

hi, you might need to set the ignition timing

one thing to suggest, a bad engine temp sensor or corroded plug.

 

2, ignition timing, it should be at 20 deg btdc

 

3, timing belt alignment, could have skipped a tooth, or is installed a tooth off by the previous mechanic.

 

search "timing belt check and adjustment" on this forum, and "the art of subaru maintenance" eisodes 7 and 8 on youtube.

 

This will give you the basis on understanding the oddity of the ea82 engine.

 

your 'tbi' setup is called 'spfi' in subaru terms (single port fuel injection)

 

after reading the timing belt article and watching the videos, you can easily check your timing marks by removing the outer covers and rotating the crank

one other thing you might try is an air filter. I changed plugs, wires, ect. However, I didn't really notice a difference until I changed the air filter. It could be clogged to the point that it can get air at half throttle, but not enough to supply full throttle. Since it is fuel injection, it could be or richening it because of an air-restriction. Just a thought. Air filter is less than or around $15, so if it works, cheap fix.

 

87roo: TBI is throttle body injection.

Another simple thing to do is replace the fuel filter.

You didn't say when or for how long it has been lacking power? Since you changed the plugs and parts or just before. Did the loss of power happen all at once or over months of driving. How about mileage on the car, and any past upgrades or repairs. Off hand I am would like to know if you get any backfire through the throttle body? If so I am thinking a valve has started to leak and you are down on compression on one cylinder. Have you done a compression check? Just a few thoughts.

if it happened after you did all that, make sure everything is tightened down. Sometimes, a spark plug is a little loose, and lets compression leak past it.

Power loss was after changing the Plug, Cap, Rotor and Fuel Filter. Ran great when parked, Idled fine but just didn't have any power when driving. Put new gas in and it seemed to run better. That was when I started getting power around 4000rpm. The next day when trying to start it it's like running on like 2 cylinder. Only runs for a short while then dies. Will check some of the suggestions. Thanks for the Help!!

check the gaps too.

Make sure the plugwires are seated on the plugs correctly. If they are ok then perhaps they got damaged when changing the plugs and a new set may fix the problem.

+1 to Miles Fox and timing belt check/replacement. My 88GL had slop in the belts and ran like cr@p untikl I changed them out. Obviously check all of the stuff you changed too.

 

You mention that it runs for a 'little while' then dies - how long/short is that? Can you feather the throttle and keep it alive? How about with your foot to thtr floor? If its only a couple of seconds that it stays alive without touching the pedal - did you have your air box open for anything? Check to make sure all of the PCV hoses are together and the air box is tightened down with the clamps. The MAF could be dirty too, giver a shot with carb cleaner. I know firsthand that if they get soiled, they will allow the car to start but then it will die pretty much right away.

 

Lastly blast a bunch of carb cleaner around your vaccum points. If you hear the RPM increase when you hit the right spot, you have found a vaccum leak.

Follow up........It turned out to be a loose distributor shaft. Got a replacement for 65.00. Replaced it runs like a champ. Once I had the other distributor out I was able to tighten the Shaft down by the screw under the rotor. Guess I should have looked there first. Cheap fix and Have a back up for other projects. Thanks guys for all the help.