1987 Corvette Fuel Injectors
Thread Starter
Heel & Toe
Joined: Oct 2019
Posts: 20
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1987 Corvette Fuel Injectors
Hey guys, I took apart my intake plenum because of a coolant leak and while I was there I wanted to check my injectors. I'm having a hard time finding the brand and kind of injectors that these are. I was gonna switch them to the Bosch 3 ones if they are stock. The numbers on the injectors are 5235211 and there is a small symbol that looks like 2 "P"s (PP). Does anyone have any idea what brand or kind these are? Also, while I have the intake manifold apart, is there anything I should specifically do while im in there? Thanks!
Safety Car
Joined: Mar 2003
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
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The stock injectors for 1987 were Bosch EV-1. They are actually very good injectors (unlike the junk Mul-Tec's that were put into use starting in 1989). Switching to the Bosch III's would not be a bad thing to do while you're in there, since you have everything apart.. The Bosch III's have 4 holes instead of one like the EV-1's which give better fuel atomization. I changed them in both my last '87 and my current '86 and noticed a smoother idle and quicker throttle response in both cars. I did not notice any increase in MPG.
The only other thing I would suggest doing would be replacing your fuel pressure regulator diaphragm. (ACDelco 214-2156, Standard Motor Prod. PR10). It's a very easy job to do while you're in there...remember, your original is 33 years old! You will need to use a tamper-proof torx bit to get the screws out. Those are the torx bits with a hole in the middle of the bit end to accommodate fitting over the little pin in the middle of the screw holes.
The only other thing I would suggest doing would be replacing your fuel pressure regulator diaphragm. (ACDelco 214-2156, Standard Motor Prod. PR10). It's a very easy job to do while you're in there...remember, your original is 33 years old! You will need to use a tamper-proof torx bit to get the screws out. Those are the torx bits with a hole in the middle of the bit end to accommodate fitting over the little pin in the middle of the screw holes.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
The above is good information, I'm running the Bosch 3 #24lb injectors in my 383 stroker motor and they are excellent injectors.. Most on here get there injectors from a company called "FIC" , they are the go to guys for injectors and Jon knows injectors better then anyone .. Let me also add that you should replace both the fuel rail crossover O-rings, and the O-rings where the fuel lines connect to the fuel rails...Im sure these O-rings are in need of replacing if they are original...WW
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Last edited by WW7; Feb 28, 2020 at 10:52 AM.
Safety Car
Joined: Mar 2003
Posts: 3,583
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
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All of the fuel rail o-rings (including both of the cold start injector o-rings) were included in the PR10 kit I purchased, so if you buy the "kit" you should not have to hunt down the individual rings.
Safety Car
Joined: Mar 2003
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
C4 of Year Finalist (stock) 2019
No. I ordered mine from a seller on ebay and nabbed it for $25.00 (made in USA), but Rockauto has them as well as some auto part stores. DO NOT buy from one from any of the major vendors - they will seriously gouge you on price. Also, do not try to go cheap and get some ebay or Amazon Chinese knock off...you get what you pay for and you'll regret you went that route..
Safety Car
Joined: May 2001
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From: Fairfax Virginia
FIC is a very popular source as is South Bay Injectors for replacement injectors. Both of these companies supply first class service and quality injectors. I would not buy injectors from an unknown entity on Ebay. Both the companies I mentioned will sell you a "matched set" of injectors and then they will stand behind them which you won't get on ebay.
Check the Fuel pressure diaphragm to be sure it is in good shape. Remove the vacuum line and smell for gasoline, if gasoline smell is present then you re-build or replace the FPR. Also check your fuel pressure at idle, it is important to be in the right range or you will have drivability issues.
Don't feel bad about a project "Growing" as you work on it. I had to replace the EGR on my car and that lead to a major top end work-over. I pulled the plenum and sand blasted it and painted it and cleaned out the insides really well and by the time I was done I had replaced the Injectors, FPR, spark plugs and wires, EGR, EGR Vacuum solenoid and cold start injector. A one day project turned into a two month project but that is not that unusual in the Corvette World.
Best regards,
Chris
Check the Fuel pressure diaphragm to be sure it is in good shape. Remove the vacuum line and smell for gasoline, if gasoline smell is present then you re-build or replace the FPR. Also check your fuel pressure at idle, it is important to be in the right range or you will have drivability issues.
Don't feel bad about a project "Growing" as you work on it. I had to replace the EGR on my car and that lead to a major top end work-over. I pulled the plenum and sand blasted it and painted it and cleaned out the insides really well and by the time I was done I had replaced the Injectors, FPR, spark plugs and wires, EGR, EGR Vacuum solenoid and cold start injector. A one day project turned into a two month project but that is not that unusual in the Corvette World.
Best regards,
Chris
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Thread Starter
Heel & Toe
Joined: Oct 2019
Posts: 20
Likes: 1
FIC is a very popular source as is South Bay Injectors for replacement injectors. Both of these companies supply first class service and quality injectors. I would not buy injectors from an unknown entity on Ebay. Both the companies I mentioned will sell you a "matched set" of injectors and then they will stand behind them which you won't get on ebay.
Check the Fuel pressure diaphragm to be sure it is in good shape. Remove the vacuum line and smell for gasoline, if gasoline smell is present then you re-build or replace the FPR. Also check your fuel pressure at idle, it is important to be in the right range or you will have drivability issues.
Don't feel bad about a project "Growing" as you work on it. I had to replace the EGR on my car and that lead to a major top end work-over. I pulled the plenum and sand blasted it and painted it and cleaned out the insides really well and by the time I was done I had replaced the Injectors, FPR, spark plugs and wires, EGR, EGR Vacuum solenoid and cold start injector. A one day project turned into a two month project but that is not that unusual in the Corvette World.
Best regards,
Chris
Check the Fuel pressure diaphragm to be sure it is in good shape. Remove the vacuum line and smell for gasoline, if gasoline smell is present then you re-build or replace the FPR. Also check your fuel pressure at idle, it is important to be in the right range or you will have drivability issues.
Don't feel bad about a project "Growing" as you work on it. I had to replace the EGR on my car and that lead to a major top end work-over. I pulled the plenum and sand blasted it and painted it and cleaned out the insides really well and by the time I was done I had replaced the Injectors, FPR, spark plugs and wires, EGR, EGR Vacuum solenoid and cold start injector. A one day project turned into a two month project but that is not that unusual in the Corvette World.
Best regards,
Chris
great. Thank you for the responses. I took the diaphragm out and looked at it. The material/ orange stuff was flacking off towards the center and I was wondering if that means it’s going bad? I’ve test idle pressure and it’s been ok but it drop suddenly when shut off. It’s goes to 0 after a few mins. I have another forum that I posted with the full detail but to sum it up, the car needs to turn over quite a bit to get it going. But if I leave it sit for a week it’s starts instantly. But 1 hr after? Hard start. Not sure. Hoping this Diaphragm could maybe solve it? I’ll post a picture of it. Thanks!
Safety Car
Joined: Mar 2003
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
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First, YES, replace that diaphragm. The coating should not be flaking off. The material is coming off of the "fuel" side of the diaphragm and heading straight for the injectors.
Secondly, you will not be able to diagnose your hard start issue properly until everything is put back together and you can diagnose your issue methodically. Can that diaphragm cause your issues? Yes. Is it a sure that that is the problem? No. Your fuel pump can cause pressure bleed down after shut off as well. So don't try to fix what you can't properly diagnose until you replace your injectors, that diaphragm, and get your car running again.
Do you have a Factory Service Manual? If not, buy one now. I can't stress the importance of owning the service manual enough. It will walk you methodically step-by-step through any problem you could encounter on your car, and save you from having to ask (and wait for) solutions on a forum that may or may not take you through the steps in the proper order required to correctly diagnose an issue.
Secondly, you will not be able to diagnose your hard start issue properly until everything is put back together and you can diagnose your issue methodically. Can that diaphragm cause your issues? Yes. Is it a sure that that is the problem? No. Your fuel pump can cause pressure bleed down after shut off as well. So don't try to fix what you can't properly diagnose until you replace your injectors, that diaphragm, and get your car running again.
Do you have a Factory Service Manual? If not, buy one now. I can't stress the importance of owning the service manual enough. It will walk you methodically step-by-step through any problem you could encounter on your car, and save you from having to ask (and wait for) solutions on a forum that may or may not take you through the steps in the proper order required to correctly diagnose an issue.