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-   -   300 ce 1989 starting problems (http://www.peachparts.com/shopforum/tech-help/12280-300-ce-1989-starting-problems.html)

sell tahsin 01-03-2001 05:54 AM


I have had this car now for around six years and have had to live with an erratic idling problem which appears without fail when the car is approaching around 80-90 degrees on the water temperature gauge. The garages that have been servicing the vehicle have never been able to find the problem.Lately I have not used the vehicle for a couple of months and had to recharge the battery as a result. I left it on charge for a couple of hour and then decided to take it for a run. As it approached the above temperature the engine began to get lumpy and hesitant on acceleration and misfiring until finally it gave up and died.Attempts to restart failed and in addition the battery went flat again. I called out a tow truck who delivered us home. I then recharged the battery overnight and in the morning the car started up without a problem. It reaches this point of warm up gets lumpy etc and dies out and efforts to restart even produce popping in the airfilter and prove useless until the temperature of the engine goes down.

I am hopeful that rectification of the the starting problem will also rectify the erratic idling I have endured for many years.

Please can somebody point me in the right direction.

LarryBible 01-03-2001 08:01 AM

This may be the classic Overvoltage Protection Relay problem. I have never had any problem with mine, but there are many discussions about this.

Do a search of all Tech Help posts for "overvoltage protection relay" to learn more.

Good luck,

sell tahsin 01-03-2001 08:20 AM


Thank you for your input where exactly is this relay on the vehicle. I have tried to locate the petrol pump relay without any luck since they are not marked as such and the manual i have has photographs. The relay compartment behind the fuse box only has 3 relays of varying size. one seems to be a triple relay another a double and the last a single . There also is a fuse like component bridging two connectors behing the largest of the relays. I have taken each out in turn and turned on the ignition and each time i could hear the fuel pump activate and the stop which i belive is normal as it pressurises the system.


yal 01-03-2001 08:45 AM

The fuel pump and OVP relay are behind the battery. The fuel pump usually has "kickdown" written on top of it. I say usually because some aftermkt fuel relays don't. The OVP has a fuse (or two) on top of it. Check the fuse(s) first before you start replacing it. OVP relay sometimes goes crazy when you jump the battery, you may have achieved the same problem by charging the battery the way you did.
Hope this helps some.

sell tahsin 01-03-2001 08:52 AM

Yal

Thank you for the information and I did initially jump start the vehicle. What is the remedy for it . Do I need to replace the component or is it resetable?

yal 01-03-2001 10:34 AM

The remedy as discussed many times on this forum is to check the fuse(s) on top of the OVP relay. Chances are you blew one. Also make sure you have an updated red top OVP relay...if you don't then it may be a good investment to get it replaced.
Also do a search for "over voltage relay" at the top right of your screen and you'll get a wealth of info.
Hope this helps further.

sell tahsin 01-04-2001 02:50 AM


I have checked the ovp relay fuses and they are ok.Would the relay itself require changing the one fitted is the red top type with two fuses. In the same area there is a section of wiring which has two inline fuses slotted in . What are they for? and would they have any bearing on the subject.

Tugging at the cables in this area certainly has an impact on the idling of the vehicle.

yal 01-04-2001 12:09 PM

I'll have to differ to the Techs on this one, but there is a thread that discussed some of the problems with the contacts underneath both OVP and/or the fuelpump relay. I am going to do a search and see if I can find it for you.


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