Car started to have mild hesitations. Suspected egr but ruled out due to symptoms at wot and above 3.1k rpm. Contiuned to drive untill syptoms got worse, wosre to point it became undriveable. Searched threw fourms for an answer. Threw my reasearch and trial and error, it developed an idle surge, almost immediately. This started soon after carb cleaner was sprayed into the intake while car was running. Since then i replaced the tps, iacv, both ect's, gutted cat (to ensure no clog) and throttle boddy gasket and hesitation still remained but then got cel 9. Replaced dizzy twice to enusre first was not bad out of box. Then ecu. Code 9 gone, heistation gone, but lacks power. If cold, car idels high and steadstilly like normal, but when iacv takes over surge continues. Ecu been reset and allowed car to idle for 10 min, but no change. Pcv valve is good and there are no vacuum leaks, that i could find other then the initial throttle body gasket which was replaced. I think im having an air to ratio problem. If i put my finger over iacv hole in tb i can get car to idle normal and rev responsibly. If i plug completely car stalls. Coolant system was flushed, but no change. There are no cels currently and ive hit a dead end. On old ecu q32 and q34 were blown if this helps. I could find nothing on google other then q31. Any help or ideas greatly appreciated. Car is 5 speed h23 with 109k. Thanks

 

Sounds like you just need to redo the ignition timing and a new iacv.

 

Iacv is new, and timing is actually on the Schedu for tomorrow, not that i thought it would have any thing to do with idle surge, but ill let you know the results. Thanks

 

You still have a vac leak somewhere. Get a propane torch and turn the gas on but don't light it, wave it all around the engine while its running.... once the idle jumps up, you have found a leak.

 

ok, got to timing this morning. had to use friend to cover iacv hole in tb to slow the rpms down due to surging idle. the 15 Degree mark lines up, but changes and completely disappears from view when more air is allowed threw iacv port and rpms change. Not a car expert, but i dont think it should do that so i shut the car off and did not adjust anything. Any ideas? Should i attempt to find a vacuum leak first or could this fluctuating timing mark be my issue?

 

You have a vaccum leak. Chase it down and fix it.

And double check your coolant as well for air still in the system, a very over looked and common Honda engine issue.

 

coolant system was flushed and bleed. I will double check for vacuum leaks again shortly before doing any thing else and relay the findings.

 

used propane to check to leaks and none found. also put propane directly into tb iacv port but it made no change. Then for *** sakes, changed fuel filter. No change

 

For the love of all cute and cuddly furry creatures in the world....... it's 'through', NOT threw!!!!!!