Pob 1 Posted August 23, 2006 About a month ago I removed the head as a Exhaust stud had snapped. The Stud was repaired and the head was skimmed (To be on the safe side) Got the engine back together and after sorting another problem its idling too fast. At cold it will start no problem and idle at 1200 to begin with then gradually increase to 2000 rpm. Once warm it will drop to around 1500-1600. I have swapped the SAD, checked the pipes. Screwed the SAD onto the metal block thing as when i got the car it the SAD was loose for some reason. The Inlet gasket has been replaced due to the first problem but the problem is still there. I've also swapped the Throttle body as I thought me faffing around with the settings on the original one could have caused it. I've kinked the SAD pipe and makes no difference, I've got the bolts in the inlet manifold. How can I check for air leaks? I carn't see how it could have one but there must be one somewhere. Any suggestions what to do next? I'm all out of ideas now Many Thanks, Dan Share this post Link to post Share on other sites
brianthemagical 1 Posted August 23, 2006 assuming it's jetronic, have you tried the idle screw in the throttle body? i think it's in for decreasing and out for increasing. failing that it could be the throttle initial position ie the butterfly could be slightly ajar. take the throttle body off, clean it up, including the idle screw, and put it back together and go from there. hope that helps. Share this post Link to post Share on other sites
Pob 1 Posted August 24, 2006 I've cleaned the throttle body, tried adjusting the idle screw and still no difference. Even if I screw it all the way in it doesn't alter the idle very much. Checked the butterfly posistion and it seems fine. Thanks for the help so far... Dan Share this post Link to post Share on other sites
Ryan 99 Posted August 24, 2006 I had a similar problem with the mi16 and it turned out to be the throttle switch. Check the connection, and that the pins haven't pushed out of the plug. Make sure the switch engages properly when you close the throttle. It could also be an air leak somewhere. Make sure all the hoses are secure and not split. Also check the bolt that holds the oil filler to the inlet as this goes right through the metal and lets air in if you leave the bolt out. Share this post Link to post Share on other sites
Rob_the_Sparky 9 Posted August 24, 2006 Sounds more like the throttle cable is too tight so throttle plate isn't quite closing. For high revs the first thing you need is air... I have been amazed at how loose is has to be to close fully! Doubt it is the old missing bolt issue as that normally makes them idle apallingly badly, rather than just a high idle. Rob Share this post Link to post Share on other sites
arry 0 Posted August 24, 2006 Doubt it is the old missing bolt issue as that normally makes them idle apallingly badly, rather than just a high idle. Sorry to jump in on Pob's thread - but which bolt is it that goes missing which causes problems? Mine's a 1.6 and idles pretty attrociously - it sits at 1600rpm warm and hunts, which is a touch annoying. Share this post Link to post Share on other sites
Rob_the_Sparky 9 Posted August 24, 2006 The bolt in question goes into the side of the manifold to hold the oil filler in place. The drilling goes straight through into the manifold so if missing you get a big air leak just where you don't want it. A sod to find if not aware of this! Rob Share this post Link to post Share on other sites
arry 0 Posted August 24, 2006 The bolt in question goes into the side of the manifold to hold the oil filler in place. The drilling goes straight through into the manifold so if missing you get a big air leak just where you don't want it. A sod to find if not aware of this! Rob !! cheers !! I'll go have a look at that tomorrow. Need to start sorting some of the car's "issues: fairly soon Share this post Link to post Share on other sites
Craigb 2 Posted August 25, 2006 (edited) The bolt in question goes into the side of the manifold to hold the oil filler in place. The drilling goes straight through into the manifold so if missing you get a big air leak just where you don't want it. A sod to find if not aware of this! Rob I fixed one of those for a friend last night ! he had been scratching his head for about a week Edited August 25, 2006 by Craigb Share this post Link to post Share on other sites
Pob 1 Posted August 25, 2006 There is a bit of slack in the throttle cable and the TPS has been swap with another. Checked the bolts & wrapped them with PTFE tape to make sure. There must be an air leak somewhere, finding it is proving difficult Thanks for all the help so far! Dan Share this post Link to post Share on other sites
futura 3 Posted August 25, 2006 Hi Pob, I have the same problem as you, and have everything inside out without success. I changed the inlet manifold gasket, cleaned everything properly before refitting and tightned bolts reasonably. A year later I am still troubleshooting this so I sprayed WD40 on the inlet bolts, to find out there were air leaks. Tightened them and some had gone pretty loose, but two of them are still leaking... Did you check yours? Share this post Link to post Share on other sites
Pob 1 Posted August 25, 2006 Hi Pob, I have the same problem as you, and have everything inside out without success. I changed the inlet manifold gasket, cleaned everything properly before refitting and tightned bolts reasonably. A year later I am still troubleshooting this so I sprayed WD40 on the inlet bolts, to find out there were air leaks. Tightened them and some had gone pretty loose, but two of them are still leaking... Did you check yours? On my engine there is only one bolt and the rest are studs.. where was the air leaking from? Around the studs/bolts or where the nut seats on the inlet Many Thanks, Dan Share this post Link to post Share on other sites
futura 3 Posted August 25, 2006 Yeah sorry my language mistake. The leaks were coming from the top two nuts: One on video here Share this post Link to post Share on other sites
Pob 1 Posted August 25, 2006 Is that making bubbles? Surely if it was drawing the air in it wouldn't bubble up like that? Thanks, Dan Share this post Link to post Share on other sites
futura 3 Posted August 25, 2006 Yeah that's how you detect air leaks You spray some WD40 and where it bubbles you have an air leak. Share this post Link to post Share on other sites
Pob 1 Posted August 25, 2006 Oh lol, I thought it caused the revs to drop due to sucking in the wd40.. shows what i know lol. I'll have a look tomorrow, Thanks, Dan Share this post Link to post Share on other sites
futura 3 Posted August 26, 2006 You're right it affects the rev too Share this post Link to post Share on other sites
futura 3 Posted August 26, 2006 but I think they go up when you spray WD40 on the air leak. Share this post Link to post Share on other sites
