Hot start faulty

Wed Mar 25, 2009 8:03 pm

I have an '87 325es and my hot start is acting up. If my engine is completely cold, it starts strong and instant, but if it is already hot, then I need to give it some gas in order to keep it from cutting out when I try and start it. Any idea what the problem is here? Thanks a lot for any help.

Wed Mar 25, 2009 9:43 pm

same thing happened me,what sort of car was it? mine was air leaks everywhere?

Sat Mar 28, 2009 2:30 pm

nmm1379 wrote:I have an '87 325es and my hot start is acting up. If my engine is completely cold, it starts strong and instant, but if it is already hot, then I need to give it some gas in order to keep it from cutting out when I try and start it. Any idea what the problem is here? Thanks a lot for any help.

My 1991 e30 318is was having a problem when starting after it had been parked with the engine hot for more than 15-20 mins.

Symptoms were as if it had no fuel in the line. Cranked over 6-8 times and then stumble and start and run fine.

I did research on the internet and found that similar problems had been posted on other BMW websites. see: http://www.bmwe34.net/Wiki/tiki-index.p ... +hot+start
I never checked with BMW in Canada for availability.

Note: The repair kit is inexpensive but costs more than its worth in shipping.
Bulky packaging. Kit consists of the replacement fuel line with the check valve already attached (you will cut this to length for your application) and some new clamps (crimped type clamps you may wish to replace with screw type clamps) and some insulation tubing and plastic nut covers (this can be discarded as you may not use this for your repair)

I finally had enough and I purchased BMW check valve p/n 16149068988 from Steve Haygood in the states. You can see his site at http://www.stevehaygood.com:80/

Pre install

Post install

Car starts without hesitation now!!!!:rolleyes:

Important Note: Do this outside not in the garage!!!!

Very simple. Disconnect the fuel pump power supply and fuel sender connectors. Takes 30min, just have everything ready, Clamps, tools, fire extinguisher and pre cut the fuel hose before you disconnect the feed line.

Be prepared for some fuel to leak back down towards the fuel pump, have some rags handy.

This retrofit can be done on all e30's that have the fuel pump in the tank under the rear seat as shown in the DIY. I did this on my 91 318is with the M42 engine. I have had no hot starting issues since the install.

Sat Mar 28, 2009 4:12 pm

Nice solution ! Not one I've seen before but definately worth investigating. Mine has similar issues when starting warm/hot - you have to crank it over for a good few seconds before it will fire - unlike every other BMW I have owned which started more or less instantly.

I have on my list to change the blue temp sensor and also get the injectors cleaned but I may try this mod as well.

Sat Mar 28, 2009 6:11 pm

318is are prone to perishing air pipes as well give them a check

Sat Mar 28, 2009 10:26 pm

Please define "air pipes" for us north american visiters

Sat Mar 28, 2009 10:47 pm

Failure of the non return valve built into the fuel pump is a well known common cause of slow starting, and is easily checked by connecting in a fuel pressure gauge.
I didn't know that BMW sell a seperate in line valve though, to save replacing the whole pump.

Sat Mar 28, 2009 10:49 pm

dark_islight wrote:Please define "air pipes" for us north american visiters

All the hoses around the intake side of the engine that don't contain coolant or fuel.

Mon Mar 30, 2009 6:42 am

thanks for all the help! will try these mods

Mon Mar 30, 2009 9:00 am

I just ordered a check valve so once done i'll let you know if it's fixed my starting issue (left more then say 20mins it's harder to start) Changed sensors and all.

Wed Apr 01, 2009 8:58 am

thatd be great, considering I probably won't do it for about a month. Thanks!