Jump to content

Classic Impreza headache problem

Recommended Posts

Hello fellow scooby owners right bare with me this is long winded and head hurting 
Ok well ive rebuilt a subaru impreza 1995 wrx from ground up complete Shell strip i never had a engine so i bought another subaru 1995 wrx that had been stood for years with a engine problem it wouldnt run unless map is unplugged so i thought not to worry ill be stripping engine anyways 

So i removed engine replaced headgaskets,and different heads i relapped all valves etc
Different inlet manifold with 
Throttle position sensor 
Idle valve
Coolant temp 
02 sensor 
Fuel filter 
Adjustable fuel reg set to 3 bar 
Vac pipes
Map sensor 
Boost sensor
Converted back to single coils 

Now ive replaced all these 3 times with ones off my friends and still same 
Ive measured voltages on throttle sensor and are within tolerences 

I can get it to run for 2 seconds lumpy and dies if i disconect throttle sensor and maf it starts no problem and ticks over sweet just cant rev obviously if i reconect while running it dies 

Connected black connectors no codes stored 

Much appriciated reading this far 
Im really hoping someone can give me a pointer something im missing 

Thanks so much

Link to comment
Share on other sites

Thanks for replying 

Sorry i should of made it clearer i replaced it with another standard v2 one so both same 

Coils are in the side

previous owner did newage conversion i thought that could be problem so converted back but still same 

If i disconnect maf and throttle sensor it starts and idles spot on no misfires just wont rev up and loads of unburnt fuel im guessin because ecu in limp mode 

I do ecu reset everytime i disconnect sensors

Link to comment
Share on other sites

Has it definitely got a jdm ecu in it ?

Changing the tps or icv can cause issues if the manual adjustment is in a different position . As the ecu thinks it's in a different position .

Have you attached the engine loom earth to the inlet manifold?

Did you reinstall the ignition igniter behind the boost solinoid bracket. As this is by passed when doing a newage coil pack conversion?

If it's not broke .....upgrade it 😊

Link to comment
Share on other sites

Def ecu for my car i run a z4 ive swapped it with a 2c i think at min its what came with the spare car i bought 

I thought same thing adjusting the tps ive used multimeter and is set to 4.8 closed and 0.9 open 

The map sensor and igniter etc ive replaced the whole piece with what came with my Shell so different to my spare car one 

Thinking about the earth i think ive bolted to manifold and not the starter 

Link to comment
Share on other sites

It definitely sounds like a electrical issue to me , seeing as it idles ok with the maf and tps unplugged.

Does seem strange that your not getting any codes up though . When you reset the ecu (I think) the boost solinoid and relays "click" ect . Does it do that ? , Ie is the reset /eml light definitely working ?

If it's not broke .....upgrade it 😊

Link to comment
Share on other sites

Def electrical not mechanical which is half good since replaced heads etc 

Yeh fans kick in and solenoids click 

If i move tps or disconect maf the codes come up when count the flashes so i know check engine light does register 

Ill check on that earth lead tomorrow

Do appriciate your time 

Im guessing i need to find a wiring diagram there must be something linking the two to put it into default setting and make it run 

Link to comment
Share on other sites

No problem ,bud .

Unfortunately sparks ain't really my thing .

there's a link to free pdf files on 1 of the first few pages of my sticky build thread on here which will have the diagrams on .

The loom earth should bolt onto the inlet manifold with a earthing "eye" just behind the start of the fuel hard lines (above cylinder 4 )

Keep us posted and best of luck

If it's not broke .....upgrade it 😊

Link to comment
Share on other sites

Quick update i moved earth to starter and fitted new plugs gapped to 0.7 and bingo starts to a degree with everything connected and revs up just something not 100% like a misfire so going to swap coils tomorrow thanks for replying savage bulldogs only you out of a 109 people who viewed this post and on scoobynet replied 

Link to comment
Share on other sites

Your welcome mate , you nearly always get a reply on here .

We like to help if possible 

Do you know if your injectors are the right ones for the ecu (phase 1 grey 380's or yellow 440's ) did you use new "o" rings when you fitted them ?

Do you know if the fpr is reading true ?

as a slight change in pressure can make a big difference to the fueling .

Thought I'd add I once connected the coil packs on cylinder 1 &3 the wrong way round [emoji55] it ran lumpy on 2 cylinders and even drove up to 3k .

If it's not broke .....upgrade it 😊

Link to comment
Share on other sites

Haha piggy sniffer 'scooby doo' amused me 

Fpr is brand new sytec one but i can test it to make sure does anyone know what pressure should be roughly

The injectors was already in the manifold 380 standard ones i am wondering which way the connectors go ones grey and ones white i think white goes to front engine 

Same with coils i believe white connector is front coils the wire dosnt seem to stretch to get them wrong way round 

cheers guys

Link to comment
Share on other sites

Iirc the tps should read 0.5-0.8v closed and 4.7-4.9v open. if it is the wrong way itll be trying to run open and closed loop the wrong way around.


switch the TPS positive and negative the oposite way around to get the sensor to read correctly

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...