AeroNautical Posted June 21, 2020 Share Posted June 21, 2020 Some backround: 88 MJ with a 98 4.0 and an obd1 conversion. 99 horseshoe intake, banks header and high flow exhaust. Bored 62 mm throttle body. Are the 24 lb mustang injectors just too much for a non stroker? When cold, it starts and runs perfectly. When hot, it starts, stumbles, is very rich and usually dies. I have to feather the throttle to keep it running, but it runs perfectly again after about 20 seconds. With stock injectors, when the engine was under load (towing or WOT), it would lose all its power. With the 24 pounders, that problem is gone. Ideas? New FPR, maintains fuel pressure and doesn't bleed down. New MAP, new iac, new O2 and new tps. Edit: It does NOT pop any engine codes, the CEL doesn't even turn on when it's doing the little song and dance I explain above. Link to comment Share on other sites More sharing options...
Eagle Posted June 21, 2020 Share Posted June 21, 2020 You're still running the Renix system? Stock injectors are 19 lb. I'd say 24 pound is too much, but you might be able to dial them in with an adjustable MAP sensor. Link to comment Share on other sites More sharing options...
cruiser54 Posted June 21, 2020 Share Posted June 21, 2020 So, maybe the original injectors weren't flowing enough because of age or something, and the ones you installed are flowing too much. Perhaps a nicely refurbished set of stock injectors or the equivalent 4 hole injectors would be a wiser choice. Link to comment Share on other sites More sharing options...
AeroNautical Posted June 21, 2020 Author Share Posted June 21, 2020 9 hours ago, Eagle said: You're still running the Renix system? Stock injectors are 19 lb. I'd say 24 pound is too much, but you might be able to dial them in with an adjustable MAP sensor. No sir, it's been completely converted to OBD1, and it was running the same 93 era stock injectors. I've heard about adjustable MAPs, I'll look into it. Thanks 1 hour ago, cruiser54 said: So, maybe the original injectors weren't flowing enough because of age or something, and the ones you installed are flowing too much. Perhaps a nicely refurbished set of stock injectors or the equivalent 4 hole injectors would be a wiser choice. That certainly sounds plausible. Any recommendation for a 93 era 4 hole injector? Link to comment Share on other sites More sharing options...
cruiser54 Posted June 21, 2020 Share Posted June 21, 2020 I have no recommendation on the 93. Only Renix. Contact info: trevor.skankfootracing@gmail.com https://www.facebook.com/Skankfoot-Racing-100901878066960/ Link to comment Share on other sites More sharing options...
AeroNautical Posted June 22, 2020 Author Share Posted June 22, 2020 11 hours ago, cruiser54 said: I have no recommendation on the 93. Only Renix. Contact info: trevor.skankfootracing@gmail.com https://www.facebook.com/Skankfoot-Racing-100901878066960/ Thanks Link to comment Share on other sites More sharing options...
cruiser54 Posted June 22, 2020 Share Posted June 22, 2020 He has all sorts of cool stuff including turbo kits. Link to comment Share on other sites More sharing options...
yxmj Posted June 22, 2020 Share Posted June 22, 2020 If the 24 lb injectors you are using are the red ones..and you find them too much for you ....here is a plug and play fix.......try changing them to the Ford four hole yellow (orange)....I run them in my 4.0's as well as my 2.5 in the YJ Here is a list compiled by someone else for junk yard use I came on a yard that had a stock of old police cars so I highlighted the ones I like.....But they are all the same. 93-94 Bronco 5.0L93-94 Bronco 5.8L92-98 Crown Victoria 4.6L93-98 Crown Victoria Police Interceptor 4.6L03 E-150 4.6L03 E-150 5.4L03 E-150 Club Wagon 4.6L03 E-150 Club Wagon 5.4L93-94 E-150 Econoline 5.0L93-94 E-150 Econoline 5.8L97-02 E-150 Econoline 4.6L97-02 E-150 Econoline 5.4L93-94 E150 Econoline Club Wagon 5.0L93-94 E150 Econoline Club Wagon 5.8L97-02 E150 Econoline Club Wagon 4.6L97-02 E150 Econoline Club Wagon 5.4L03 E-250 5.4L93-94 E-250 Econoline 5.8L97 E-250 Econoline 4.6L97-02 E-250 Econoline 5.4L03 E-350 5.4L03 E-350 Club Wagon 5.4L93-94 E-350 Econoline 5.8L97-02 E-350 Econoline 5.4L93-94 E-350 Econoline Club Wagon 5.8L97-02 E-350 Econoline Club Wagon 5.4L00-02 E-450 Econoline Super Duty 5.4L00-02 E-450 Econoline Super Duty Stripped 5.4L97-98 Econoline Super Duty 5.4L00-04 Excursion 5.4L97-02 Expedition 4.6L97-02 Expedition 5.4L93-94 F-150 5.0L93-94 F-150 5.8L93-94 F-150 Lightning 5.8L97-03 F-150 4.6L97-03 F-150 5.4L93-94 F-250 5.0L93-94 F-250 5.8L97-99 F-250 4.6L97-99 F-250 5.4L99-03 F-250 Super Duty 5.4L93-94 F-350 5.8L99-03 F-350 Super Duty 5.4L92-97 Grand Marquis 4.6L94 Thunderbird LX 4.6L94 Cougar XR7 4.6L96-04 Mustang GT 4.6L98-01 Lincoln Navigator 5.4L91-93 Lincoln Town Car 4.6LHere are the part numbers for the injectors:OEM 0280150909 BOSCH OEM 0280150939 BOSCH OEM 0280150943 BOSCH OEM CM-4714 MOTORCRAFT OEM CM-4718 MOTORCRAFT OEM CM-4719 MOTORCRAFT OEM F0TZ-9F593-C FORD OEM F0TZ-9F593-DA FORD OEM F1TZ-B FORD OEM F1VY-A FORD OEM FOTE-B1A FORD OEM FOTE-D1A FORD OEM FOTE-D5A FORD OEM FOTZ-C FORD Link to comment Share on other sites More sharing options...
AeroNautical Posted June 24, 2020 Author Share Posted June 24, 2020 That's quite the list, thanks! They are the silver and green injectors. Link to comment Share on other sites More sharing options...
75sv1 Posted June 25, 2020 Share Posted June 25, 2020 I see the new FPR (Fuel Pressure Regulator). Is this on the fuel pump or the fuel rail? What PSI does the fuel pump deliver? Also the leak down of it (might have that term wrong)? Did you change the fuel pump? I am using the 12 hole injectors. I think they might give a bit better performance over the 4-hole Fords. They would need adapters for the '98 wiring. They are plug-n-play for 2000-up. Link to comment Share on other sites More sharing options...
AeroNautical Posted June 25, 2020 Author Share Posted June 25, 2020 2 hours ago, 75sv1 said: I see the new FPR (Fuel Pressure Regulator). Is this on the fuel pump or the fuel rail? What PSI does the fuel pump deliver? Also the leak down of it (might have that term wrong)? Did you change the fuel pump? I am using the 12 hole injectors. I think they might give a bit better performance over the 4-hole Fords. They would need adapters for the '98 wiring. They are plug-n-play for 2000-up. The fuel pump is brand new also. There isn’t a bleed down issue, it maintains 39 psi with no vacuum, and 30 psi with. Does anyone sell those injector adapters? Link to comment Share on other sites More sharing options...
75sv1 Posted June 25, 2020 Share Posted June 25, 2020 I bought them off a guy that goes by Cobra Marty. I'd probably check Ebay. That pressure seems low to me. Is you Fuel Pressure Regulator on the Fuel Rail or on the Fuel Pump? The latter XJs had the Fuel Pressure Regulators on the Fuel pump. I think they go to a higher pressure. I forget which regulator will match to the older Fuel Rail. It will increase the pressure to I think 50 psi. A bit out of my real on this, though. Look here: https://www.ksuspensionfab.com/store/p22/Remanufactured%3A_12_Port_Upgraded_Injectors.html#/ Link to comment Share on other sites More sharing options...
AeroNautical Posted June 25, 2020 Author Share Posted June 25, 2020 5 minutes ago, 75sv1 said: I bought them off a guy that goes by Cobra Marty. I'd probably check Ebay. That pressure seems low to me. Is you Fuel Pressure Regulator on the Fuel Rail or on the Fuel Pump? The latter XJs had the Fuel Pressure Regulators on the Fuel pump. I think they go to a higher pressure. I forget which regulator will match to the older Fuel Rail. It will increase the pressure to I think 50 psi. A bit out of my real on this, though. Look here: https://www.ksuspensionfab.com/store/p22/Remanufactured%3A_12_Port_Upgraded_Injectors.html#/ Thanks for the link. The OBD1 era fuel rail with the return line is stock at 39 psi with no vacuum, and 30 at idle. I think your thinking of the returnless fuel rail on the 98, 99 era XJ. The regulator is on the rail. But all things considered, I'm having an extremely rich environment, so low fuel pressure certainly isn't the issue I wouldn't think. Link to comment Share on other sites More sharing options...
75sv1 Posted June 25, 2020 Share Posted June 25, 2020 OK, but your not running that era fuel injectors. I might be off on this, though. And Yes, I am thinking of the newer OBD2 fuel pressure. I was looking into this from the 99+ intake upgrade. Jordan on MallCrawling did this upgrade and latter injectors. Also, upgrade d with HESCO adjustable regulator. Then someone mentioned an 93 or 95 Eagle Vision regulator. ??? Edit: Here's the Link: http://mallcrawlin.com/forum/showthread.php?6355-4-0L-99-intake-manifold-swap-with-REAL-DYNO-NUMBERS! See the last couple of pages. Link to comment Share on other sites More sharing options...
yxmj Posted June 25, 2020 Share Posted June 25, 2020 If this is the silver and green injector your talking about........then you have a typo......not 24 LB.....they are 42 LB Link to comment Share on other sites More sharing options...
AeroNautical Posted June 26, 2020 Author Share Posted June 26, 2020 16 hours ago, yxmj said: If this is the silver and green injector your talking about........then you have a typo......not 24 LB.....they are 42 LB Wow, 42 pounder? At what rail psi? These are what I’m using: Link to comment Share on other sites More sharing options...
yxmj Posted June 26, 2020 Share Posted June 26, 2020 Ok here is the specs for that injector https://www.injectorplanet.com/products/denso-2741 Again I would suggest going with the Yellow /Orange 4 hole.....plug and play and never had a problem Link to comment Share on other sites More sharing options...
AeroNautical Posted June 27, 2020 Author Share Posted June 27, 2020 11 hours ago, yxmj said: Ok here is the specs for that injector https://www.injectorplanet.com/products/denso-2741 Again I would suggest going with the Yellow /Orange 4 hole.....plug and play and never had a problem I just picked some up today from the JY. I’ll clean them up with my sonic cleaner and 9volt some carb cleaner through them, and install tomorrow. Here’s hoping! Link to comment Share on other sites More sharing options...
silvertwinkiehobo Posted June 27, 2020 Share Posted June 27, 2020 Two vehicles I didn't see listed are the late '90s Explorer and Mountaineer 5.0's; the injectors are the skinny 4-holers, and they're the same as the ones on the Modular engines. Link to comment Share on other sites More sharing options...
AeroNautical Posted June 28, 2020 Author Share Posted June 28, 2020 On 6/26/2020 at 11:07 AM, yxmj said: Ok here is the specs for that injector https://www.injectorplanet.com/products/denso-2741 Again I would suggest going with the Yellow /Orange 4 hole.....plug and play and never had a problem After grabbing 8 from a JY, 2 fail and one leak, I've finally gotten some good ones installed. So far so good, it runs just fine. I'll have to get it up to temp and try to start it to make sure it actually fixed the problem, but I have no power loss with these like I did with the stock injectors. Thanks for the suggestion. Link to comment Share on other sites More sharing options...
yxmj Posted June 29, 2020 Share Posted June 29, 2020 Yes that is the problem with the JY .......possible to get junk.....glad they are working for you Link to comment Share on other sites More sharing options...
AeroNautical Posted July 12, 2020 Author Share Posted July 12, 2020 So, it appears the yellow/orange 4 hole ford injectors pretty much fixed the problem after the computer relearned them. Thanks for the help guys, my Jeep runs well again. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted July 14, 2020 Share Posted July 14, 2020 Just lookup an injector calculator. Remember that a 24lb Injector is rated at a higher fuel pressure that our systems are set for so you really aren’t getting 24lbs from it. I believe our actual fpr are set for 38lbs with no vacuum??? Link to comment Share on other sites More sharing options...
silvertwinkiehobo Posted August 20, 2020 Share Posted August 20, 2020 39-40 PSI with no vacuum. On Ford, it's a 10 pound difference with vs. without vacuum, and Chrysler is 9 PSI. As for injectors, I am incorrect about the 4-hole injectors; the 5.0 and 4.6 19# injectors are '710' last three digits, and the Ford 4.0 V6 19# ones, IIRC, are '739' last three digits. Link to comment Share on other sites More sharing options...
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