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Mike, Technician
Category: Car
Satisfied Customers: 39198
Experience:  Tech Expert
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I have a 1990 dodge ramcharger se150 with 5.9l v8. Recently

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I have a 1990 dodge ramcharger se150 with 5.9l v8. Recently it has had slight trouble starting but more importantly, at low speeds the transmission slips in and out of different gears with a thud and sometimes the engine stalls. The coil, plugs, fuel pump, have been replaced recently. Trans has full oil level. The engine occasionally surges slightly when idling. I live in UK so expertise is limited to me.

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Hello and Welcome -

My name is XXXXX XXXXX Im happy to help / advise you ..

Can I just ask - what has been done / checked so far - other than what you have mentioned... Have you had any plug in diagnostics done etc ?

Too - what is the mileage?

Also - what was the condition of the trans fluid when you checked that?

Rgds, MIKE........................................
Customer: replied 4 years ago.

Hi Mike,

Thank you for coming back to me. I did check the trans fluid yesterday and it was full, clear, red. I also check the engine oil, clearish and brown - no burning. The fuel pump was changed 18 months ago with a new one. The mileage is 154000. At the same time the fuel pump was changed, it had a new coil and spark plug wires, new plugs, air filter, and wiper motor.


I do not have a plug in diagnostic as I am in the United KIngdom. There are Jeep and Dodge dealers around for the UK sales but I don't know if they can help on a vehicle this old. Advice? I do use the on board computer system and I have a 1989 full service manual. The latest codes are:



17 Thermostat which I have a replacement for



There is an ABS light on in the truck and Maint Req light. Looking in the manual, the Maint Req could be triggered by the EGR having problems.


Yesterday, I noticed a slight leak around the battery which I will change this weekend. It has a new muffler, cat convertor, the air line from the pump is properly connected. Everything works


It has been running brilliantly until a few days ago and it seems to struggle to keep running. It idles with an occasional surge (five to ten seconds - very slight) and then cuts back. Sometimes, it just stops running.


Parts can be bought from the States but there is more than a 100% mark-up on duty and taxes so I have to make it worth my while and be correct when I buy them.


Hello again -

Thank you for your reply and further info -

Ok - as far as the idle issues go - I assume you have checked the pipework - breather system/ vacuum lines etc - and for any air ingress / leaks - any of the above not in proper order will cause that at low revs... If you haven't checked - that all needs doing.

Other than that - the biggest issue by far that will cause your idling issues is that the throttle body needs a thorough clean internally - this is best done with a "carb cleaner" spray or such like - ensuring it sprays through all the ports etc - and be sure to clean the edges of the plate / throttle plate - open it to clean that - and also where the plate sits when closed - They get a dirt build up - or stick on the spindle and will cause such issues as you have..

Other than that - you do have the fault code 42 Smec - Injector and module faults etc.. So long as that is not an old / historic code - it could well be relevant... Im going to give you a link to a wealth of info on that ...more than I can type !... so this will be helpful for you on this fault code ( and others )... for that - click HERE. Scroll down to the post 85 model / paragraph.. To - there is a lot more info there for you as I mention - as well as parts supplier too ;)

Code 37 that you have may or may not be important-- it is related to the transmission ( torque converter I will mention in a moment- so you need to follow through on that as follows..
Code 12 you can ignore.

Back to the trans then -

As far as the transmission issues go though which seems to be the main issue ( and can even affect idling too --- as a knock on effect )... This really could at this stage be anything in the transmission / system. I doubt to be honest that its anything on the control side - but of course the wiring / connections etc on the circuit should be checked - but its most likely internal.. either a torque converter or solenoid fault.

You have checked the fluid and thats good - no signs of major issues - so its as above. And then - to be 100% honest - at this point you really are best having an Auto specialist take a look. Usually they will start by opening it up - just removing the pan - and inspecting to any debris - metal filings and such like. They will clean the internal filter and flush it - and re try it. .. then go from there as / if necessary... it could be that will cure it !... but if not - they are fully equipped - both with the knowledge that is needed - and the test equipment and toolery to effect a repair as needed - at much cheaper costs than a general garage would charge. Often dealers and garages send such troubles to these people - as the alternative is replacement - which is always a horrendous cost - compared to repairs as needed....

So thats what I would recommend on this one now -to work through to getting this sorted for you -- thats the best overall / cheapest , cost effective way forward for you.

Check the things I have mentioned on the engine - and the throttle body first...

Let me know how you get on - and Im always happy to help you further as / if needed..

Very best Rgds, MIKE.

Let me know if you need anything more on this at all -

>>> >> > Meantime...

Please do click on the OK rating to Excellent ratings service for me now at this point , Thank you for that... and you can get back to me anytime if you need / wish..

Best Rgds, MIKE.

Mike, Technician
Category: Car
Satisfied Customers: 39198
Experience: Tech Expert
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Customer: replied 4 years ago.

Thank you for the information and the excellent response. I am not at the house for a few days but on my return Saturday, I will check the things you mentioned and see if there is an improvement. I would like to stay in touch with you so there is a consistency in the progress. let me know if that is god for you.


Hello again Tony -

Thank you for your reply... Im very pleased to have helped you ..

Thats fine yes - Im always here if you need anything.

Best Rgds, MIKE.