Rumbling/Shuddering on Cold Start.

Re: Rumbling/Shuddering on Cold Start. (Adrian)

Fri, 09 May 2014 00:16:58 GMT

I use caltex 98 all the time and lately I haven't had the problem at all. Seems to happen for a week or so then go away for a while.

Re: Rumbling/Shuddering on Cold Start. (Reddtarga)

Thu, 08 May 2014 17:53:07 GMT

Lumix
My 97 NA use to do this. In my case I discovered it was the Caltex Vortex 98 fuel causing my cold start problems. So for an experiment, I filled up with BP Ultimate 98, no shuddering. The next tank I tried Shell V-power 98, no shuddering. I went back to Caltex Vortex 98 and the car shuddered on the first cold start every morning until the tank was empty. I could turn it off and restart the car with no problems on the second start. No idea why but using a different fuel has worked for me, possibly something you can try when you fill up next?

Ha ha, that's interesting.
It so happens that I have just started using Caltex Vortex 98, (I had not used it previously) and now I think about it that coincides with this problem starting. I've also never had the problem before.
Next time I'll fill up with Shell or BP to see what happens.

When I find out, I'll post up the result.

Re: Rumbling/Shuddering on Cold Start. (Reddtarga)

Thu, 08 May 2014 17:35:49 GMT

Head gasket
Where abouts is the cold start injector

On the end of the intake manifold to the right of the throttle body (with the banjo connector)

Re: Rumbling/Shuddering on Cold Start. (Head gasket)

Thu, 08 May 2014 15:13:46 GMT

I'll be replacing my cold start injector sometime next week, my car has the same problem. Ill let you know my result

Re: Rumbling/Shuddering on Cold Start. (Eric)

Thu, 08 May 2014 13:51:54 GMT

Mine does the same no matter on the fuel. Dosnt really do it in summer. 1990 jdm Na

Re: Rumbling/Shuddering on Cold Start. (Head gasket)

Thu, 08 May 2014 11:39:48 GMT

Where abouts is the cold start injector

Re: Rumbling/Shuddering on Cold Start. (Mrskylighter)

Thu, 08 May 2014 09:44:08 GMT

Could you try unplugging the cold start injector wiring plug and see if it makes it worse or the same?
If the same then your problem is either the injector or a coolant sensor for the cold start (if there is one on the NA engine)

Re: Rumbling/Shuddering on Cold Start. (Lumix)

Thu, 08 May 2014 09:40:22 GMT

My 97 NA use to do this. In my case I discovered it was the Caltex Vortex 98 fuel causing my cold start problems. So for an experiment, I filled up with BP Ultimate 98, no shuddering. The next tank I tried Shell V-power 98, no shuddering. I went back to Caltex Vortex 98 and the car shuddered on the first cold start every morning until the tank was empty. I could turn it off and restart the car with no problems on the second start. No idea why but using a different fuel has worked for me, possibly something you can try when you fill up next?

Re: Rumbling/Shuddering on Cold Start. (Reddtarga)

Thu, 08 May 2014 08:46:42 GMT

My car has started doing the same thing, and I simply switch off and restart, as per Wiz's post.
That fixes it, so it looks like the CSI is faulty.
The climate has now turned cold, which is probably why it is now more noticeable.

Re: Rumbling/Shuddering on Cold Start. (Adrian)

Sat, 03 May 2014 16:31:53 GMT

My car does this sometimes as well. 97 NA.

Cold start, it sounds like it's running on 3 cylinders. Really rough and low idle. If I apply some throttle to try and coax it into life, it doesn't like it and will misfire. If I leave it for a few minutes it will just start idling like normal. If I turn it off and restart straight away it always starts fine the 2nd time.

No idea what it is and it's been doing it on and off for at least a year or 2. No other issues so I've just left it alone.

Re: Rumbling/Shuddering on Cold Start. (Admin)

Thu, 01 May 2014 21:55:08 GMT

Possibly a worn out fuel pump

Re: Rumbling/Shuddering on Cold Start. (wiz)

Thu, 01 May 2014 14:24:37 GMT

Next time it does this try turning it off (as it is rumbling etc.), wait around 10 seconds and then try starting it again. If it then starts without a problem it is bound to be a cold start injector problem. This used to happen with my SW20 occasionally but it didn't concern me as I just turned it off and tried again and it was fine.

If it is doing it every time though it's probably wise to get cold start injector checked out or replaced.

Re: Rumbling/Shuddering on Cold Start. (Reddtarga)

Thu, 01 May 2014 09:32:16 GMT

Rumbling/Shuddering on Cold Start. (Pipinhot)

Wed, 30 Apr 2014 18:47:05 GMT

I have a 1990 SW20 N/A import.

And on a cold start in the morning it doesn't fire properly for about 5 seconds, its not spluttering, more like failing to raise RPM. It shudders and rumbles the car then its all good, its got new NGK plugs, just copper ones. new engine mount, had the head gasket replaced, and a carbon clean.....

it has been sitting for a bit, after the water pump blew and we replaced that. So i'm confused as to what it could be.
Do i need to burn off any leftover gunk or something.

Need options????