Boxer stalling and no start

Read thru forum but still thought I'd ask...last year, had issue where car started, but when stepping on gas, would stall unless easily pushing accelerator up to 2k and then it would accelerate but not sound/feel 'right' up to 4k. Eventually car would stall and die and not restart. Replaced both fuel pump fuses and car ran normally.

Day before yesterday, car ran for 40 min (ie, got warm), and then when back to garage. Had same issues as above. Checked both fuel pump fuses and they were good, but replaced them anyway after sanding connectors. No luck and starting.

Yesterday, car cranked up, but had same issues as above. Pulled fuel pump relays checking all three for clicking when putting 12V and ground power to pins 85 and 86. Also checked for resistance across 85 and 86, and it was in normal range 50-120. However, did not check 30 to 87 with 12v and ground connected to 85 and 86. Could the relays still be bad?

Will replace the three relays 2 x 0332 014 113 for left and right, and 1 x 0332 204 101 for control. Will any 5 pin square 12v 30a (85 86 87 87 30) and 12v 30a (85 86 87 87a 30) suffice (ie, RY88 for 0332 014 113 and RY30 for 0332 204 101)?

Any of ideas on what's causing these issues? Pumps must be getting power and working else the car wouldn't have started after sitting over night. I replaced Dinoplex with MSD 20 years ago and have had no issues.

 

Is your Boxer completely (euro) stock, or has it had "quasi-Lambda" modification (i.e., a frequency valve added) to be US-legal?

Also, in addition to needing good electrical contact at the terminals holding the fuse ends, the whole riveted plate structure from the male spade where the wire attaches to the metal terminal holding the fuse end on both ends needs good electrical contact -- you might need to solder/improve/replace all of those connections. Bottom line would be to measure the voltage on the wire exiting the fuse(s) at the bottom and going to the fuel pump = should be at least a good +12V relative to ground when the engine (alternator) is running. Alternatively, if you measure the voltage from the female spade terminal of the wire at the top of the fuse to the female spade terminal of the wire at the bottom of the fuse = should be a very low DC voltage (like not even a few tenths of a volt).

 

Thank you, will check voltages.

Not sure about ["quasi-Lambda" modification (i.e., a frequency valve added)]. What is it and how would I know I've had the mod done?

 

The frequency valve is a small device with a 2-pin electrical connector that would be added into the control pressure plumbing usually near the fuel distributor(s). However, I should've confirmed just what Boxer model that you have (this wouldn't apply to a BB512 nor 365 Boxer), and, if you aren't in the US, it wouldn't apply -- your Profile isn't accessible. If you have a BB512i, and can post a picture of the engine bay, it should be easy to tell.

Here is an example of an added frequency valve on a BB512i:

Image Unavailable, Please Login

And here's an example of a frequency valve added to a 412:
Image Unavailable, Please Login

 

Just saw this note...boxer is 83 512bbi US conversion...it was E.P.A.ed and D.O.T.ed by E.L.C. Imports in San Jose in 1984...changed the 3 relays but still have same problem...felt the relays clicking when touching them while cranking...car started when cold but coughed and backfired when adding power below 2000 rpm...as long as I kept rpm above 2000, I could add throttle and car would rev normally...idled normally for a while as car warmed up...eventually idle went up and down around 1000, stalled while idling, and would not restart...when disconnecting ground side of battery, connector was too hot to touch...now that I have new relays, will check voltages as suggested earlier...any additional thoughts on what this issue might be?

 

You really need a VOM from Home depot and a CIS fuel pressure testing kit to proceed say from Amazon. That is unless you want to guess and throw parts at it. As much as anyone here can tell you it will not replace getting data that can lead to a resolution. https://www.amazon.com/CTA-Tools-3420-Compatible-Injection/dp/B008FJXA3M/ref=sr_1_5?crid=1SIP2PX0BAEJ8&dib=eyJ2IjoiMSJ9.7D5zitcwIWgOoMT308pfcKuzh0BUqkhimAvHY_9oiTHLZmwmwb4HUwZKhNav4k1YiNesun6AF93q0yqdCnQFJhBTRA6U34Zw9AacqM3x2z7NrKEcb3cX5t15k-rZSatJ55o30mCFctEiPhHx5UWRXjUZr6y4rT-7t0ewp_MV8K5rZY7bKdG4bYlfXYtsW3We7d85MTkhZTeaBLDosWLu78ioUg6Z9y9Jrji8Ccb9osA.DEls4_v7wmYQxL0roTdi4jMMuko5ehNDkJ5BCJIBnvg&dib_tag=se&keywords=CIS+pressure+test&qid=1717012427&sprefix=cis+pressure+test+%2Caps%2C136&sr=8-5

 

Rebuilding Mangusta (suspension/wheel bearings now), so finally made it to Boxer. Attached are various pics of K-J, motor, CB panel, and relay panel. I looked on line to see what Frq Val might look like but didn't find a match. Do the the K-Js on my Boxer have Frq Val? I did notice on CB panel, there is a separate group of relays that have been stuffed above CBs. If there are Frq Vals, since these relays above CB panel appear to be after the fact, could one of them be the Frq Val relay? Found no O2 sensor on either side of headers or exh.
Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

 

I would say "no" -- and not having O2 sensor(s) anywhere also indicates "no".

I believe virtually all Boxers did get the FV modification to get into the US originally (and that requires a +12V power source and a separate aftermarket ECU so some extra electrical bits are added), but many have been unmodified -- and some of the (now disused) electrical bits get left behind.

But back to your original problem -- if you don't have the FV modification, an electrical problem there doesn't exist. Have you measured the voltage between the male spade of your fuel pump fuses with the huge red wire at the top and the male spades at the bottom where the beige and beige-black wires go to the fuel pumps? Should be near 0V DC when the engine is running, but there's about 20A coming in the huge red wire, and very common for the plastic to melt up there and loosen the riveted connection (so they are still mechanically OK, but are electrically poor).

 

Will check voltages as you suggest. Where do I look to check for the melted plastic and loosened connection? Right where the large red wire connects on top to the male spade?

 

More where the rivets connect to the metal pieces, but a closer examination of your photo shows this may not be an issue -- typically, the rivets connect to a separate metal piece on the backside of the plastic, but yours looks like there is a direct metal connection between the top pieces on the front side of the plastic (which would be a good improvement). Still doesn't hurt to measure the voltage from the top male spade terminal to the bottom male spade terminals just to confirm things are OK.

 

Have you closely checked the distributor cap for even the slightest hairline cracks? I was experiencing the same exact symptoms that you are describing. Before sending, towing, the car into the shop and as a last resort, I replaced the distributor cap. Now starts and idles perfectly! Once I replaced it, I could see several hairline cracks on the underside of the cap. Makes sense with the exhaust being just below.

 

I also had a equal problem with my carbed car. there it also was the distributor cap. I found this out in the very dark garage. when I started the engine a friend of mien have seen ingintion spraks outside at the cap. after renew this cap no problem anymore.
but I think your problem is somewhere else