Ok I have been having issues with my swap ever since I installed it. I know the engine is good since I removed it from another one of my cars to put it into my 1998 EK. The swap is a 1997 B18b1 with a 1999 GSR Transmission running off an OBD1 P75 ECU.

So the issues start like this, sometimes when I start the car up from cold it will either jump to 1500rpm and after about 10 seconds it will have dropped to 900rpm. Other times it will just start up at like 1000rpm and drop to 800-900 around the same time frame. After this happens it will sometimes drop off to like 400rpm and then slowly climb back up to normal idle and repeat itself over and over in about 30 second intervals.

Once the car is warm it will idle fine but every so often the engine will stumble and drop the idle to 400rpm and climb back up similar to the cold start idle but doesnt seem as bad or as frequent. Now when driving the car there is a noticeable lack of power around 2000-3000rpm and once it hits 3000rpm it pulls perfectly fine. Right now im starting to think its something internally or maybe a jumped tooth on the timing belt. I just removed my Engine harness to make sure all my wiring is correct and it checked out 100%, the only problem i see is the EVAP canister plug has 2 wires and the light green w/white stripe is connected to nothing. I cant find any info on where this wire goes but i doubt it would effect the engine that much.

So im asking all of you for advice on what the problem may be? Maybe its something internally? Maybe the Timing belt jumped a tooth? Maybe something could be missing in my wiring but i doubt it. Please give me any input you have.

 

Adjust it to top dead center and see if it lines up, maybe it did jump a tooth.

Just the other day my b18c1 jumped a tooth because a rag got caught in it (dont ask haha).

The engine would idle fine and when u give it gas its decent too, but when it drops down again to idle it bogs for 2-4 seconds before it idles normal again. 1 tooth jumped from the timing belt on the exhaust side and you can see what happened.

Did you touch a lot of the wiring by the ECU? When doing my last swap I had to replace/swap all my old ECU pin plugs to a better looking ECU pins plugs. The old one was hacked up as I was getting experience :D. Well good luck, PM me if you think I can help you with anything else.

 

hmmm your issue sounds similar to mine, sometimes when you let off the gas and let the rpms drop to where it should be at idle speed it will drop below and bog a little and then jump back up. I am starting to think I have have jumped a tooth. The only thing is I have checked and the cam gears line up with each other so maybe i either jumped a tooth on both or maybe on the crank sprocket?

All the wiring is good, i did it myself and every connectio nis soldered and tested for resistance. I thought maybe i had crossed a wire but guess I didnt. Looks like I may have to do a TB and water pump change and check that my timing is on.

 

Bump

 

TTT

 

hey bro my computer hasn't been working but i definitely assure you that you are not correctly aligned. Set the crank pulley on the white line and check that both cam gears are top dead center. The 2 marks should line up too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by evilcivilian &raquo;</TD></TR><TR><TD CLASS="quote">hey bro my computer hasn't been working but i definitely assure you that you are not correctly aligned. Set the crank pulley on the white line and check that both cam gears are top dead center. The 2 marks should line up too.</TD></TR></TABLE>

I know the cams line up but didnt take the time to check the crank pulley but I will do it when the weather is a bit nicer.

 

I had the same problem with my swap. I was idleling irregularly like you were describing only i would get out of vtech every once in a will. My mechanic told me there was a misfire fail code and when everything was diagnosed it turned out i just had a blow gasket.

 

well i dont have any codes now, which gasket was blown? headgasket?

 

yes the head gasket

 

hmmm, normally if your headgasket goes u would see smoke out ur exhaust or oil/coolant mixed and i have neither of those symptoms

 

in my case i only had a small oil leak

 

doubt its the head gasket, leaning towards timing belt being off a tooth or something of that nature.

 

top for advice

 

Ok I just checked the Timing belt stuff by making sure the white mark on the crankshaft pulley lined up with the lower timing cover mark and that the cam gear marks were directly inline with each other. It checks out PERFECT so now im stuck as to what could be causing my irratic idle issues.

Basically it seems like on a cold start it will start up idle high for a second and then drop down low, most of the time stalling out. Once I drive the car and it warms up it will usually idle fine without issues but once i restart it after letting it sit the same issue happens with the idle. Now most people might say its a vacuum leak or the FITV is the culprit but it has been checked and there arent any issues with it. Another reason im sure it isnt anything to do with the cold start mechanism (FITV) is because i still have a brutal power loss in the lower rpms which is most noticeable in 1st, 2nd and 3rd gears.