Tyson Posted January 22, 2012 Share Posted January 22, 2012 (edited) Firstly it's a 1994 1.4 8v hi torq manual astra. When it's really cold its a bugger to start having to turn it over up to 5 times whilst revving it to start. It starts but cuts out and the engine management light flashes then goes off. But after a few starts it goes and is fine but if you turn it off it before its warm it does the same again. However once its warmed up it will start first time no problem. Forgot to mention if the weather is warm it will start first time, I have had it for 6 months and never had a problem it just does this in really cold weather. Anyone got any ideas? I was thinking damp contacts or the fact it could do with a service but anyone had this before. Edited January 22, 2012 by Tyson (see edit history) Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 23, 2012 Author Share Posted January 23, 2012 Anyone? Quote Link to comment Share on other sites More sharing options...
neo2810 Posted January 23, 2012 Share Posted January 23, 2012 I'm having a similar problem with the Supra, and reckon it's a cold start or cold injection sensor (although I don't know if the NA has one)??! I'm going to change the spark plugs and change the sensor if it exists, then move on to fuelling system. Quote Link to comment Share on other sites More sharing options...
absz Posted January 23, 2012 Share Posted January 23, 2012 Sounds like coolant temperture sensor. you can access the fault codes using a link wire on the diagnostic plug just do a search on the web for correct pins. Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 24, 2012 Author Share Posted January 24, 2012 Right I used this guide to read the codes http://www.c-vox.com/archive/index.php/t-1352.html With the engine off all I get is code 85 which is immobiliser wrong signal. With the engine on it quickly flashes 15 times then flashed slowly without a pause 8 times over and over. Whilst bridged it idles at 1500 rpm and dips down momentarily to 500 ish then back up again. If I take out the paper clip it idles normally. Quote Link to comment Share on other sites More sharing options...
absz Posted January 24, 2012 Share Posted January 24, 2012 Are you bridging the correct pins, seems odd how the idle creeps. Quote Link to comment Share on other sites More sharing options...
Shane Posted January 25, 2012 Share Posted January 25, 2012 The hardened valve seats slowly sink into the head meaning that the valve clearances close up until the valves start to leak a little, and especially when cold. Result: Not enough compressin for a nice start on a cold day. Run a feelergauge through under each lobe of the cam when the valve should be closed and this will tell you if this is why, obviously do this when the engine is stone cold. If it is and if its the engine I think it is, you just need to re-shim, easy job. I think the error code thing could be a red herring and something else. Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 25, 2012 Author Share Posted January 25, 2012 Are you bridging the correct pins, seems odd how the idle creeps. Yes mate the ones with the brown and brown / yellow wire, the ones you highlighted above. Quote Link to comment Share on other sites More sharing options...
absz Posted January 25, 2012 Share Posted January 25, 2012 The hardened valve seats slowly sink into the head meaning that the valve clearances close up until the valves start to leak a little, and especially when cold. Result: Not enough compressin for a nice start on a cold day. Run a feelergauge through under each lobe of the cam when the valve should be closed and this will tell you if this is why, obviously do this when the engine is stone cold. If it is and if its the engine I think it is, you just need to re-shim, easy job. I think the error code thing could be a red herring and something else. Might be wrong but i'm sure they are hydraulic lifters and not shims,the head on these engines were designed for unleaded fuel so the valve seats are case hardened. might be worth resetting the fault code by disconnecting the battery for 5mins then run the engine for a while and read the fault codes again. Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 25, 2012 Author Share Posted January 25, 2012 .... Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 25, 2012 Author Share Posted January 25, 2012 Might be wrong but i'm sure they are hydraulic lifters and not shims,the head on these engines were designed for unleaded fuel so the valve seats are case hardened. might be worth resetting the fault code by disconnecting the battery for 5mins then run the engine for a while and read the fault codes again. will have another go today Quote Link to comment Share on other sites More sharing options...
movistar Posted January 26, 2012 Share Posted January 26, 2012 The hardened valve seats slowly sink into the head meaning that the valve clearances close up until the valves start to leak a little, and especially when cold. Result: Not enough compressin for a nice start on a cold day. Run a feelergauge through under each lobe of the cam when the valve should be closed and this will tell you if this is why, obviously do this when the engine is stone cold. If it is and if its the engine I think it is, you just need to re-shim, easy job. I think the error code thing could be a red herring and something else. This was on the 1.7 dtl engine.... Quote Link to comment Share on other sites More sharing options...
movistar Posted January 26, 2012 Share Posted January 26, 2012 Disconnect the cold start switch then start the vehicle as this will fool the ecu thinking the engine is cold.if it starts first time then you know it's the sensor.this must be done on a cold engine, on a hot engine it will be overfueling and will be very had to start. Cold start switch is a two terminal block either blue or black. Quote Link to comment Share on other sites More sharing options...
Tyson Posted January 26, 2012 Author Share Posted January 26, 2012 Disconnect the cold start switch then start the vehicle as this will fool the ecu thinking the engine is cold.if it starts first time then you know it's the sensor.this must be done on a cold engine, on a hot engine it will be overfueling and will be very had to start. Cold start switch is a two terminal block either blue or black. Cheers dude will give it a go, where abouts is it may I ask? Quote Link to comment Share on other sites More sharing options...
movistar Posted January 26, 2012 Share Posted January 26, 2012 (edited) ....look at this link I found when I google the engine type to try and get a pic for you. http://pariswells.com/blog/tag/vauxhall-astra-engine-coolant-temperature-sensor although this is a mk4 and your is a three. Is it a multipoint injection? Several places if I can recall without looking at my paperwork, could be at the back of the inlet manifold or in the head just above the alternator bracket. Good luck! Edited January 27, 2012 by movistar (see edit history) Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.